Know Your 'Rafale'

Picard

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How? I'm not sure on that. Covering the inner hot plates by outer plates is a simple cheap technique which many jets have used.
Basically, a portion of air flow is redirected not through the engine, but around it. It then cools the engine itself, and exits through an area between inner and outer nozzle. This helps both dissipate the hot exhaust by mixing it with cooler air and also cool down the outer nozzle / isolate it from the hot exhaust.
 

Bhartiya Sainik

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Basically, a portion of air flow is redirected not through the engine, but around it. It then cools the engine itself, and exits through an area between inner and outer nozzle. This helps both dissipate the hot exhaust by mixing it with cooler air and also cool down the outer nozzle / isolate it from the hot exhaust.
I know what u r mentioning but the current images in visible & IR spectrum proove that it is far easier said than done, especially in 4th gen jets. So it does help but it is not enough in 4th gen jets.
I have an idea how stealth engine nozzle would work which require additional series of cooling equipments but the leaner slim-trim 4th gen jets including Rafale simply don't have it, hence the gen gap. While 5th gen jets deploy series of cooling methods whose theory people know but exact implementation is top secret. Hence obviously the basic diagrams don't show certain secret components.

1649867298649.png


> In a default scenario, at any given altitude the plume is surrounded by ambient air at a certain normal/cool temperature through which the plume is visible in IR & visible spectrum.
The plume is a huge trail of turbulent gases whose diameter immediately increases upon exiting the engine. Hence it is a conical trail like seen in visible spectrum where cooler background terrain, houses, etc become hazy. This is natural physics & fluid dynamics which even 5th gen stealth jets also can't get rid of.
1649855064595.png

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1649857393291.png


> Now if we just introduce a higher diameter cylindrical shell around engine compared to a sealed airframe, that air will cool the engine by getting heated by engine body. This means this air is at an intermediate temperature b/w ambient & plume now. Hence if the plume was visible through ambient air then obviously it will still be visible through higher temp. air layer now. It is like the plume is surrounded by many hair dryers which won't affect visibility of plume behind it.
Check videos of thermal footage of hair dryer which is seen hot, the heated air flow cannot be seen but that hot air upon striking a wall, curtain, hair or something gets heated & visible but the background is not obstructed by the heated air exiting the hair dryer.




The only benefit is that engine body is getting cooled otherwise earlier that engine heated all components & air sealed inside airframe with poor or no ventilation making the rear fuselage hot & visible to IR sensors.
So simply passing a layer of air benefits engine & airframe but not its plume bcoz the IR & visible cameras can still see through it.
1649860809301.png


Even a higher bypass ratio civil engine doesn't hide the core plume, then military engine has lower bypass ratio. From this thermographic image itself it is clear that it is so easy to spot a big yellow airliner against a cool blue atmosphere, its plume may not be even required.

1649860999322.png


In order to actually give a shielding effect this layer of air needs to be cooled lower than ambient temperature. It is like miniaturizing a home AC & fitting it beside the engine & making the bypass air processed through it. And more such ACs are required to cool the entire airframe. This AC is called HX or Heat eXchanger & there are series of HX in all jets but they are usually used to prevent overheating of equipment & HVAC control. There are different types of HX like Fuel-air HX, Fan-air HX, Fuel-coolant HX, air-coolant HX, air-oil HX, oil-coolant HX, etc. So 5th gen jets require more # of HXs, coolant, pumps, associated plumbing & more avionics code for comprehensive cooling management means more cost & space required than 4th gen jets which are cheaper, slimmer & simply don't have more space.
1649867720957.png


In the M88 engine the path of bypass air is highlighted in yellow color which passes within the inner panels.
The outer panels are at higher diameter/circumference level. And there is no connection or path b/w the bypass air path at lower dia/circum level & inner-outer panels gap.
1649859877828.png


Neither the engine has extra HX & associated tubing, connection holes. The current tubes & pipes are for fuel, engine oil, hydraulic oil, bleed air. The tubing at back are for hydrallic actuators of nozzle panels.

1649859979674.png


Nor the engine bay has extra HX & associated tubing, connection holes, the inner surface is smooth. There are other pics available at different angles.

1649860086926.png


The airframe will have to be inflated slightly to add additional cooling equipment framework.
The nozzle part will have to be redesigned entirely.
The engine may require modification depending upon which air to be drawn for cooling processing - the intake-fan-air or the compressor bleed-air. Some air is drawn in b/w boundary-layer-separator & fuselage but it is used for cockpit HVAC, avionics/sensors cooling & areas in forward half of fuelage.
Theoretically all this can be done as part of F5/6 MLU but will it be done is a different thought.
 

Picard

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I know what u r mentioning but the current images in visible & IR spectrum proove that it is far easier said than done, especially in 4th gen jets. So it does help but it is not enough in 4th gen jets.
It is not enough in any jets. You simply cannot have an aircraft that is propelled with jet engine and especially capable of supersonic flight, yet is also stealthy in IR spectrum.

Jet aircraft that was the most stealthy in IR spectrum is probably F-117, but I would not advise placing air-to-air missiles on that thing...

I have an idea how stealth engine nozzle would work which require additional series of cooling equipments but the leaner slim-trim 4th gen jets including Rafale simply don't have it, hence the gen gap. While 5th gen jets deploy series of cooling methods whose theory people know but exact implementation is top secret. Hence obviously the basic diagrams don't show certain secret components.
You cannot simply say "4th generation" vs "5th generation" as if it is a catch-all. Also, "top secret" is one of those bullshit excuses I am really tired of hearing.

Moving on...

This is precisely what Rafale does. As I have already explained, Rafale's M88 engine has additional cooling channel as well as an external nozzle. And unlike F135's nozzle, M88's nozzle partly shields internal nozzle and exhaust plume from outside observer located to the side.

In fact, IR signature was specifically one of important requirements for M88:
untitled (free.fr)
Additionally, the M88 has been optimised so that its small infrared signature does not compromise the Rafale’s overall IR signature
That being said, F135 does have higher bypass ratio and, as you noted, ceramic coating on the nozzle. But higher bypass ratio as well as aerodynamic differences also mean that F-35 needs higher power setting than Rafale to achieve any given speed, so actual IR signature comparison would likely be advantageous to Rafale.

> In a default scenario, at any given altitude the plume is surrounded by ambient air at a certain normal/cool temperature through which the plume is visible in IR & visible spectrum.
The plume is a huge trail of turbulent gases whose diameter immediately increases upon exiting the engine. Hence it is a conical trail like seen in visible spectrum where cooler background terrain, houses, etc become hazy. This is natural physics & fluid dynamics which even 5th gen stealth jets also can't get rid of.
I am aware of that. Moving on...

> Now if we just introduce a higher diameter cylindrical shell around engine compared to a sealed airframe, that air will cool the engine by getting heated by engine body. This means this air is at an intermediate temperature b/w ambient & plume now. Hence if the plume was visible through ambient air then obviously it will still be visible through higher temp. air layer now. It is like the plume is surrounded by many hair dryers which won't affect visibility of plume behind it.
Check videos of thermal footage of hair dryer which is seen hot, the heated air flow cannot be seen but that hot air upon striking a wall, curtain, hair or something gets heated & visible but the background is not obstructed by the heated air exiting the hair dryer.
Which is why Rafale's M88 is designed in such a way that inner nozzle is not just smaller than the outer nozzle, but also recessed relative to it. The end result is that the outer nozzle hides inner nozzle as well as the hottest areas of the exhaust jet plume from view, at least when seen from frontal ~180° arc.

F135 does have a cooling layer and separate nozzles, but the outer nozzle is extremely close to the inner nozzle, which means that it doesn't hide the plume at all.

> Now if we just introduce a higher diameter cylindrical shell around engine compared to a sealed airframe, that air will cool the engine by getting heated by engine body. This means this air is at an intermediate temperature b/w ambient & plume now. Hence if the plume was visible through ambient air then obviously it will still be visible through higher temp. air layer now. It is like the plume is surrounded by many hair dryers which won't affect visibility of plume behind it.
It will affect aircraft's overall IR signature on several levels:
1) Surrounding airframe will heat less which means that aircraft will be less visible from frontal and side aspects
2) Internal nozzle is hidden from the view, which means that hottest part of the engine is hidden.
3) Hottest part of the exhaust plume is hidden from the view, which means that signature of the exhaust is also reduced.
4) External nozzle, one that is visible, is being isolated from the exhaust plume by the bypass air.

F135 does a similar thing, except it doesn't hide the hottest part of the plume anywhere as well as M88 does - or at all, really.

> Now if we just introduce a higher diameter cylindrical shell around engine compared to a sealed airframe, that air will cool the engine by getting heated by engine body. This means this air is at an intermediate temperature b/w ambient & plume now. Hence if the plume was visible through ambient air then obviously it will still be visible through higher temp. air layer now. It is like the plume is surrounded by many hair dryers which won't affect visibility of plume behind it.
Check videos of thermal footage of hair dryer which is seen hot, the heated air flow cannot be seen but that hot air upon striking a wall, curtain, hair or something gets heated & visible but the background is not obstructed by the heated air exiting the hair dryer.
Hair dryer is not a good comparison to jet engine...

The only benefit is that engine body is getting cooled otherwise earlier that engine heated all components & air sealed inside airframe with poor or no ventilation making the rear fuselage hot & visible to IR sensors.
So simply passing a layer of air benefits engine & airframe but not its plume bcoz the IR & visible cameras can still see through it.
Even a higher bypass ratio civil engine doesn't hide the core plume, then military engine has lower bypass ratio. From this thermographic image itself it is clear that it is so easy to spot a big yellow airliner against a cool blue atmosphere, its plume may not be even required.
Wrong. Exhaust plume is not the same temperature throughout. The hottest part is the one closest to the nozzle. So while, yes, preventing aircraft skin from heating up is a massive benefit, it is not the only one.

Also, your "simply passing a layer of air benefits engine & airframe but not its plume bcoz the IR & visible cameras can still see through it" outright contradicts the graphic you had provided in the very post I'm quoting now (3rd quote in this post, from the top).

In order to actually give a shielding effect this layer of air needs to be cooled lower than ambient temperature. It is like miniaturizing a home AC & fitting it beside the engine & making the bypass air processed through it. And more such ACs are required to cool the entire airframe. This AC is called HX or Heat eXchanger & there are series of HX in all jets but they are usually used to prevent overheating of equipment & HVAC control. There are different types of HX like Fuel-air HX, Fan-air HX, Fuel-coolant HX, air-coolant HX, air-oil HX, oil-coolant HX, etc. So 5th gen jets require more # of HXs, coolant, pumps, associated plumbing & more avionics code for comprehensive cooling management means more cost & space required than 4th gen jets which are cheaper, slimmer & simply don't have more space.
And you just wrote that cooling down a layer of air doesn't matter...

And if you will discuss aircraft and not just engines, then being slimmer helps with IR signature because it means that you need lower engine setting for the same speed. F35 has dry thrust of 27000 lbf compared to Rafale's 2x11000 lbf (22000 lbf total), yet Rafale is at least M 0,2 faster than F-35 when cruising in combat configuration (if you assume that F-35 can actually supercruise at M 1,2, which I have found no proof of). This means that comparison is not 27000 lbf vs 2x11000 lbf, but rather 27000 lbf vs however much Rafale requires for M 1,2.
 

Bhartiya Sainik

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It is not enough in any jets. You simply cannot have an aircraft that is propelled with jet engine and especially capable of supersonic flight, yet is also stealthy in IR spectrum.

Jet aircraft that was the most stealthy in IR spectrum is probably F-117, but I would not advise placing air-to-air missiles on that thing...
Yes it seems it may not be possible to fool mother nature & full IR stealth may not be possible to avoid IRST but still this is just the beginning of aerospace tech & we have indefinite future to go. So what matters is which country leads in science & technology by a generation.
From turbo-prop to turbo-fan/jet today we are in era of ramjet & scramjet. So what kind of hybrid jet engine we will see, hopefully in our lifetime, is a surprise to come.

You cannot simply say "4th generation" vs "5th generation" as if it is a catch-all. Also, "top secret" is one of those bullshit excuses I am really tired of hearing.
There are overlaps b/w each gen but levels of gen obviously exists. Just like Rafale cannot be compared to older 2nd & 3rd gen Mirage series. In fact Rafale F4.2 can't be compared to its prototype in 1980s.
It doesn't matter who is tired of hearing what. Like i said all that matters is which country leads & maintains secrecy for as long as possible & which country lags behind. EU couldn't make a 5th gen jet & had to move on to FCAS & Tempest.

This is precisely what Rafale does. As I have already explained, Rafale's M88 engine has additional cooling channel as well as an external nozzle. And unlike F135's nozzle, M88's nozzle partly shields internal nozzle and exhaust plume from outside observer located to the side.

In fact, IR signature was specifically one of important requirements for M88:

Which is why Rafale's M88 is designed in such a way that inner nozzle is not just smaller than the outer nozzle, but also recessed relative to it. The end result is that the outer nozzle hides inner nozzle as well as the hottest areas of the exhaust jet plume from view, at least when seen from frontal ~180° arc.
Precisely? How? Where? Someone show us by labeled diagram & pics.
As Rafale importers & operators now who would be more happier than us to have the good stuff?
But from the high rez images of nozzle from rear & side it doesn't seem there is any cooled air tubing & release holes unless you or someone could show through a labeled diagram. There are only panel actuator assemblies b/w the gap of outer & inner panels.
1649893213128.png

1649893327148.png

Every fighter jet engine has a low bypass channel but that's opening inside the nozzle, not b/w the gap. Where is the cooling channel? There should be an opening hole in the rear half of the body from which ducts should be connected to the gap but where are they? These small tightly bent tubes above are for hydrallic actuators, not for high speed streamlined air.

For example F-15's earlier nozzle's actuator assembly was fully exposed
1649900728015.png


But now all engines nozzle come with additional cover

1649903750758.png


That being said, F135 does have higher bypass ratio and, as you noted, ceramic coating on the nozzle. But higher bypass ratio as well as aerodynamic differences also mean that F-35 needs higher power setting than Rafale to achieve any given speed, so actual IR signature comparison would likely be advantageous to Rafale.
F135 does have a cooling layer and separate nozzles, but the outer nozzle is extremely close to the inner nozzle, which means that it doesn't hide the plume at all.
F135 does a similar thing, except it doesn't hide the hottest part of the plume anywhere as well as M88 does - or at all, really.
I'm not even comparing to F-35 particularly. I have actually criticized its huge exhaust & compared its afterburner plume to SR-71.
But it has extra HX system framework for cooling, also the F-22.


It will affect aircraft's overall IR signature on several levels:
1) Surrounding airframe will heat less which means that aircraft will be less visible from frontal and side aspects
2) Internal nozzle is hidden from the view, which means that hottest part of the engine is hidden.
3) Hottest part of the exhaust plume is hidden from the view, which means that signature of the exhaust is also reduced.
4) External nozzle, one that is visible, is being isolated from the exhaust plume by the bypass air.
U r repeating my theory explanation but i don't see the implementation. Nozzle gap doesn't seem to be connected to any cooling channel unless someone can show by labled pic.


Hair dryer is not a good comparison to jet engine...
It was an analogy to show if an IR camera can see a hot air flow separately & if background is obstructed or the hot air is still transparent. In absence of HX treatment, the bypass air cooling the engine will become hotter before exit than it was during intake. Like i said it will be at intermediate temp. b/w ambient & plume.

Wrong. Exhaust plume is not the same temperature throughout. The hottest part is the one closest to the nozzle. So while, yes, preventing aircraft skin from heating up is a massive benefit, it is not the only one.
What wrong? When did i say plume has same temp. throughtout? I'm showing all the diagrams & pics, u think i don't understand?

Also, your "simply passing a layer of air benefits engine & airframe but not its plume bcoz the IR & visible cameras can still see through it" outright contradicts the graphic you had provided in the very post I'm quoting now (3rd quote in this post, from the top).
U r unable to comprehend my explanation which does not contradict the graphic which was the only one i could find through Google Images. It is a simple color diagram which a high-school kid would make, not an engineer. I said that it is far easier said than done bcoz it requires additional set of equipments & framework which requires additional space who's implementation was not considered for 4th gen jets.

And you just wrote that cooling down a layer of air doesn't matter...
I said just simply passing a layer of air (without HX treatment) doesn't matter bcoz it will absorb engine's heat & will be at intermediate temp. b/w ambient & plume. Hence for actual shielding the ambient air need to be cooled down further through HX system framework which 4th gen jets don't have. They have HX only for cockpit HVAC, avionics & some aux equipments but not for extended cooling & shielding plume.


And if you will discuss aircraft and not just engines, then being slimmer helps with IR signature because it means that you need lower engine setting for the same speed. F35 has dry thrust of 27000 lbf compared to Rafale's 2x11000 lbf (22000 lbf total), yet Rafale is at least M 0,2 faster than F-35 when cruising in combat configuration (if you assume that F-35 can actually supercruise at M 1,2, which I have found no proof of). This means that comparison is not 27000 lbf vs 2x11000 lbf, but rather 27000 lbf vs however much Rafale requires for M 1,2.
5th gen jets are bulkier than 4th gen bcoz they carry weapons & more fuel, more sensors, more auxilliary equipments (including cooling HX system) internally, simple. That increases the weight hence they need a better engine too to maintain T/W ratio.
Why the hell are u shifting focus to comparing performance of F-35 & Rafale when i have never done that. Please do it with that American member. I myself said that Rafale is a very agile jet & will beat almost every non-TVC jet in gunfight, it gave tough time even to F-22.
 

Picard

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Yes it seems it may not be possible to fool mother nature & full IR stealth may not be possible to avoid IRST but still this is just the beginning of aerospace tech & we have indefinite future to go. So what matters is which country leads in science & technology by a generation.
It is not that simple...

There are overlaps b/w each gen but levels of gen obviously exists. Just like Rafale cannot be compared to older 2nd & 3rd gen Mirage series. In fact Rafale F4.2 can't be compared to its prototype in 1980s.
It doesn't matter who is tired of hearing what. Like i said all that matters is which country leads & maintains secrecy for as long as possible & which country lags behind. EU couldn't make a 5th gen jet & had to move on to FCAS & Tempest.
What matters is facts and characteristics, not labels. If you remove all-aspect stealth from definition of a "5th generation" fighter, then suddenly Rafale becomes 5th generation. Nevermind that generations are not a good estimate of capability. Second-generation MiG-21 was objectively superior to third-generation F-4 and F-111 in air combat role, and could hold its own against fourth-generation F-18 when in hands of a capable pilot.

Precisely? How? Where? Someone show us by labeled diagram & pics.
As Rafale importers & operators now who would be more happier than us to have the good stuff?
But from the high rez images of nozzle from rear & side it doesn't seem there is any cooled air tubing & release holes unless you or someone could show through a labeled diagram. There are only panel actuator assemblies b/w the gap of outer & inner panels.
Bypass air doesn't go through tubing... it simply wraps around the engine.

Cpu8L2oXgAATJRv.jpg


For example F-15's earlier nozzle's actuator assembly was fully exposed
Eh, that was because nozzle cover kept falling off...

U r repeating my theory explanation but i don't see the implementation. Nozzle gap doesn't seem to be connected to any cooling channel unless someone can show by labled pic.
I am not repeating anything, and as usual, you are completely missing the point. I was merely listing the benefits of having a separated external nozzle akin to what M88 has, and only the last point actually requires a cooling channel to be present. All other benefits are present even with normal engine setup.

It was an analogy to show if an IR camera can see a hot air flow separately & if background is obstructed or the hot air is still transparent. In absence of HX treatment, the bypass air cooling the engine will become hotter before exit than it was during intake. Like i said it will be at intermediate temp. b/w ambient & plume.
And in that case, even cooling will not help.

What wrong? When did i say plume has same temp. throughtout? I'm showing all the diagrams & pics, u think i don't understand?
Yes, in fact I do think you don't understand. If you did you would have understood my point: that because inner nozzle is smaller in diameter, separate and recessed relative to the outer nozzle, it means that not only does outer nozzle not get heated up (as much) by the engine exhaust, but also shields both the inner nozzle and the hottest part of the exhaust plume from view. This alone would be enough to significantly reduce aircraft's IR signature from frontal and side aspects.

U r unable to comprehend my explanation which does not contradict the graphic which was the only one i could find through Google Images. It is a simple color diagram which a high-school kid would make, not an engineer. I said that it is far easier said than done bcoz it requires additional set of equipments & framework which requires additional space who's implementation was not considered for 4th gen jets.
I am not unable to comprehend your explanation, but rather, you are contradicting yourself - and in general are just throwing random facts in my direction, most of which you do not seem to comprehend.

The graphic outright lists "exhaust flame surrounded by cooler air" as being an important factor in reducing IR signature. If it contradicts what you are trying to say, do not use it.

I said just simply passing a layer of air (without HX treatment) doesn't matter bcoz it will absorb engine's heat & will be at intermediate temp. b/w ambient & plume. Hence for actual shielding the ambient air need to be cooled down further through HX system framework which 4th gen jets don't have. They have HX only for cockpit HVAC, avionics & some aux equipments but not for extended cooling & shielding plume.
Design of engine and the exhaust, and even airframe, will have more impact than any cooling system. In fact, I suspect that F135's cooling mechanics are intended less for stealth and more to prevent overheating.

F135 has a high bypass ratio, which resulted in - among other things - comparatively low thrust-to-weight ratio. In attempt to compensate for the poor design for air-to-air combat, inlet temperature had to be increased. As it is, it is 25% higher than that of M88 - which does have benefits, but also very significant drawbacks. So are these cooling systems really there for stealth, or to cope with an extremely hot engine?

So in other words, fact that the air is cooled down doesn't matter nearly as much as you might think, because it will not stay cooled down. Where do you think all that heat goes?

5th gen jets are bulkier than 4th gen bcoz they carry weapons & more fuel, more sensors, more auxilliary equipments (including cooling HX system) internally, simple. That increases the weight hence they need a better engine too to maintain T/W ratio.
Why the hell are u shifting focus to comparing performance of F-35 & Rafale when i have never done that. Please do it with that American member. I myself said that Rafale is a very agile jet & will beat almost every non-TVC jet in gunfight, it gave tough time even to F-22.
F-35 is bulky even for a 5th generation fighter, and it is slow besides.

We are comparing IR signatures of fighters. Performance matters there, because IR signature is in large part a product of gaining that performance. You will notice I have not said a peep about turn rates, wing loading and other aspects of performance. Everything I had listed was connected to engine and levels of thrust required.

Or to explain it more simply: fighter that might seem to have higher IR signature on paper may actually have lower IR signature during normal operations if it can achieve same performance with lower throttle setting.

Capisci?
 

Bhartiya Sainik

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It is not that simple...
I also said it is easier said than done

What matters is facts and characteristics, not labels. If you remove all-aspect stealth from definition of a "5th generation" fighter, then suddenly Rafale becomes 5th generation. Nevermind that generations are not a good estimate of capability. Second-generation MiG-21 was objectively superior to third-generation F-4 and F-111 in air combat role, and could hold its own against fourth-generation F-18 when in hands of a capable pilot.
Facts & characteritics have to be explained & marketed using labeled infographic, pics, diagrams.
Why should someone remove the characteristic of stealth from definition of 5th gen? It is like altering definition of human & comparing to apes. As i said already that gens have overlaps in capabilities so MiG-21 or any other jet could be usable is 1 aspect like interception or BVR, it can be fitted with jammers, improved cockpit, etc, but might loose in dogfight. But older jets require big MLU to match newer jets.
Our IAF is using MiG-21 bcoz of blunder mistakes of past monarch govt., not bcoz of capability of MiG-21, we have called it "flying coffin" sinces last 2-3 decades.


Bypass air doesn't go through tubing... it simply wraps around the engine.

View attachment 150776
I don't understand French. Do you want me to give diagrams in Russian or Chinese?
What u r showing is a compressor/turbine blade made with better materials & coatings to withstand high temperatures to increase life of engines. Also with internal perforations for cooling. Otherwise a small cracked broken piece can destroy the engine.
1649955571518.png

1649955924511.png



I am not repeating anything, and as usual, you are completely missing the point. I was merely listing the benefits of having a separated external nozzle akin to what M88 has, and only the last point actually requires a cooling channel to be present. All other benefits are present even with normal engine setup.
Since 1990s i'm knowing all the benefits u listed but i just wanna see the connection b/w outer channel of M88 & the nozzle gap which is not there.
1649945526439.png



And in that case, even cooling will not help.
It helps that's why there are multiple diagrams explaining series of HX deployed to comprehensively cool the airframe, engines, equipments, shield plume.


Yes, in fact I do think you don't understand. If you did you would have understood my point: that because inner nozzle is smaller in diameter, separate and recessed relative to the outer nozzle, it means that not only does outer nozzle not get heated up (as much) by the engine exhaust, but also shields both the inner nozzle and the hottest part of the exhaust plume from view. This alone would be enough to significantly reduce aircraft's IR signature from frontal and side aspects.
In school & college we all saw few teachers who had great knowledge but they had bad explanation & presentation skills. Some simply read the books & students dozed off.
I understand ur point fully theoretically & as Rafale operators we would be so happy to have a good feautre. I also said that the inner nozzle without outer cover looks like some kind of circular panel light in IR spectrum being constatntly heated. But that's taking care of airframe, not plume.


I am not unable to comprehend your explanation, but rather, you are contradicting yourself - and in general are just throwing random facts in my direction, most of which you do not seem to comprehend.
The graphic outright lists "exhaust flame surrounded by cooler air" as being an important factor in reducing IR signature. If it contradicts what you are trying to say, do not use it.
The graphic shows the basic theory but the M88 cutaway diagram doesn't show connection b/w outer bypass channel & nozzle gap. So there is the contradiction, not in my explanation.
After providing high rez image of nozzle gap also u can't point out any connection or release holes bcoz all there is to see is actuator assemblies.


Design of engine and the exhaust, and even airframe, will have more impact than any cooling system. In fact, I suspect that F135's cooling mechanics are intended less for stealth and more to prevent overheating.
F135 has a high bypass ratio, which resulted in - among other things - comparatively low thrust-to-weight ratio. In attempt to compensate for the poor design for air-to-air combat, inlet temperature had to be increased. As it is, it is 25% higher than that of M88 - which does have benefits, but also very significant drawbacks. So are these cooling systems really there for stealth, or to cope with an extremely hot engine?
So in other words, fact that the air is cooled down doesn't matter nearly as much as you might think, because it will not stay cooled down. Where do you think all that heat goes?
F-35 is bulky even for a 5th generation fighter, and it is slow besides.
Again u r shifting focus to F-35. We all know now how much u hate F-35. I have also criticized F-35's plume, what more do u want? They might have solution to current side-effects but it will increase cost of F-35. A small example, the A & C models don't have TVC like F-22.
In every gen, every product is having some outcomes or side-effects & again engineers think if it can be eliminated to reduced to minimum. But cost of soultion to every outcome has to be seen also.
The proposed FCAS looks so different than Rafale, why? The French/EU team (like Tempest team) will also start giving more info in near future on FCAS which will also showcase improvements & then again there will be critics like you "suspecting" FCAS.
Any highly electronic jet, be it MLUed 4++, 5th, 6th gen, will require considerable cooling. And i have repeated that "comprehensive" cooling by series of types of HXs is required to cope with airframe, engine, equipments, HVAC, plume, being showed in the 3in1 diagram i shared.



We are comparing IR signatures of fighters. Performance matters there, because IR signature is in large part a product of gaining that performance. You will notice I have not said a peep about turn rates, wing loading and other aspects of performance. Everything I had listed was connected to engine and levels of thrust required.
No, i'm not comparing fighters in any way. My original post focuses only on Rafale, that too "Indian" version, that too its engine only. May be it is inferior to French Rafale & doesn't have the engine feature u claim.


Or to explain it more simply: fighter that might seem to have higher IR signature on paper may actually have lower IR signature during normal operations if it can achieve same performance with lower throttle setting.
RCS can be measured in sq.m. but i have not seen any info mentioning IRS.
Also there is no international metric or standard for throttle setting.
 

Picard

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Why should someone remove the characteristic of stealth from definition of 5th gen? It is like altering definition of human & comparing to apes. As i said already that gens have overlaps in capabilities so MiG-21 or any other jet could be usable is 1 aspect like interception or BVR, it can be fitted with jammers, improved cockpit, etc, but might loose in dogfight. But older jets require big MLU to match newer jets.
Not always... Vietnamese MiG-21s had shown themselves more than able to match US F-4 and F-105 in air combat, despite not having any kind of such MLU.

I don't understand French. Do you want me to give diagrams in Russian or Chinese?
What u r showing is a compressor/turbine blade made with better materials & coatings to withstand high temperatures to increase life of engines. Also with internal perforations for cooling. Otherwise a small cracked broken piece can destroy the engine.
Ignore the turbine blades. What matters is the engine cutaway. Blade image is there simply because I couldn't find any better image.

Since 1990s i'm knowing all the benefits u listed but i just wanna see the connection b/w outer channel of M88 & the nozzle gap which is not there.
I was not able to find it, beyond this image which shows IR signature differential:
M88-4.jpg


It helps that's why there are multiple diagrams explaining series of HX deployed to comprehensively cool the airframe, engines, equipments, shield plume.
First, cooling can only help so much. You do know that ambient temperature of the air at altitudes where air combat usually happens is well below what any cooling system will do?



-30 degrees Celsius at 15 000 ft, and -60 degrees Celsius at 30 000 ft. Both F-35 and Rafale have a service ceiling well above 30 000 ft.

So while we are talking about IR signature reduction measures here, it has to be kept in mind that "IR stealth" is actually an oxymoron.

Second, as I have already explained: F-35 is a hotter aircraft to begin with. It has a much hotter and more powerful, single engine. It also has inferior aerodynamics, which means that it has to be at higher throttle than Rafale for the same speed. So at best, all these cooling systems will help it approach Rafale's IR signature, at least when Rafale is in air-to-air configuration.

I understand ur point fully theoretically & as Rafale operators we would be so happy to have a good feautre. I also said that the inner nozzle without outer cover looks like some kind of circular panel light in IR spectrum being constatntly heated. But that's taking care of airframe, not plume.
Depending on the aspect, it also takes care of the plume. As I have already mentioned, plume is not equally hot throughout. So from frontal aspect at least, fact that there is a double nozzle will have massive impact.

Again u r shifting focus to F-35. We all know now how much u hate F-35. I have also criticized F-35's plume, what more do u want? They might have solution to current side-effects but it will increase cost of F-35. A small example, the A & C models don't have TVC like F-22.
No, i'm not comparing fighters in any way. My original post focuses only on Rafale, that too "Indian" version, that too its engine only. May be it is inferior to French Rafale & doesn't have the engine feature u claim.
I am using F-35 to show why merely discussing "IR suppression measures" is not enough. Besides, you were the one to bring F-35 (and other "5th generation" fighters) into this.

RCS can be measured in sq.m. but i have not seen any info mentioning IRS.
Also there is no international metric or standard for throttle setting.
Throttle setting can be measured in, essentially, percentages of thrust. When anybody mentions throttle settings in fighters, that is what they usually mean.
 

Bhartiya Sainik

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Not always... Vietnamese MiG-21s had shown themselves more than able to match US F-4 and F-105 in air combat, despite not having any kind of such MLU.
I'm not an aviation or military historian so i can't comment on the Vietnam air battles.
But in that era MiG-21 was a formidable interceptor & US pilots might have suffered from overconfidence.

Ignore the turbine blades. What matters is the engine cutaway. Blade image is there simply because I couldn't find any better image.
You highlighted different concept bcoz this blade cooling is applicable only to high pressure compressor & turbine blades where temp. is high, not to the bypass channel in theory where ambient air is drawn from fan inlet like u said in 1st reply. Bypass means bypassing the compressor & turbines. And then i said that the bypass ambient air needs to be further cooled & an entire series & types of HX framework is involved.

I was not able to find it, beyond this image which shows IR signature differential:
View attachment 150889
It seems to contradict the screenshot which i shared where inside the exhaust a ring of concentrated heat is seen which would be this outer channel which u say. A cooling channel of air cannot glow hottest.
If there is really a cooling channel then it seems France is keeping the better engines for their domestic jets, not for exported ones.

1649984437608.png

1649984794281.png



First, cooling can only help so much. You do know that ambient temperature of the air at altitudes where air combat usually happens is well below what any cooling system will do?

-30 degrees Celsius at 15 000 ft, and -60 degrees Celsius at 30 000 ft. Both F-35 and Rafale have a service ceiling well above 30 000 ft.
So while we are talking about IR signature reduction measures here, it has to be kept in mind that "IR stealth" is actually an oxymoron.
At high altitude bcoz the air temp. drops, an uncooled jet would be more porminent, hence the comprehensive cooling required. Otherwise so many diagrams from R&D sites, so many scientists & engineers working & already implemented equipment is waste of tax payer's money & hence all 6th gen development should also be stopped then. But this is not the pinnacle of mil. aviation, it is just the starting. A better Sword & then a better Shield are alternate aspects of repeatitive developments.
100 years back during WW era nobody thought we would reach where we are today.


Second, as I have already explained: F-35 is a hotter aircraft to begin with. It has a much hotter and more powerful, single engine. It also has inferior aerodynamics, which means that it has to be at higher throttle than Rafale for the same speed. So at best, all these cooling systems will help it approach Rafale's IR signature, at least when Rafale is in air-to-air configuration.
How many time will i repeat that i'm also not fan of F-35's bigger engine & plume & also not of its dogfighting performance? The VTOL requirement has forced it into single bigger engine implementation. otherwise it would have been a 2-engine jet like J-31/35 & also with F-22 like nozzles or perhaps further improved.
May be a futuristic engine will have distributed apertures like F-117 or Harrier's Rolls Royce engine but also with afterburning & supercruise capability.

Depending on the aspect, it also takes care of the plume. As I have already mentioned, plume is not equally hot throughout. So from frontal aspect at least, fact that there is a double nozzle will have massive impact.
Shrouded nozzle (w/o comprehensive cooling) is a small, cheap, common add-on till 4th gen jets, not sufficient beyond that.
From where enemy will be detected or not detected is not known hence only frontal aspect cannot be relied upon. Bcoz the inner nozzleis always hot even at low speeds & non-afterburning level, that's all the outer nozzle takes care of.

I am using F-35 to show why merely discussing "IR suppression measures" is not enough. Besides, you were the one to bring F-35 (and other "5th generation" fighters) into this.
I mentioned briefly in a generic way that the idea of comprehensive cooling is part of stealth/5th gen jet design. 4th gen jets don't have additional space required for additional equipement.
I'll discuss F-35 in the F-35 thread.

Throttle setting can be measured in, essentially, percentages of thrust. When anybody mentions throttle settings in fighters, that is what they usually mean.
But same % level of 2 engines are not same.
M88 100% dry thrust is 50KN
F-135 100% dry thrust is 125KN
AL-41F 100% dry thrust is 87KN
All engines have different dimensions, weight, compression stages, combustion chambers, nozzles, additional teachniques. Hence there is no global ISO standard to measure & rank engine design.
So throttle setting cannot be a measure of overall jet's performance.
Anyways this is not relevant to my original post or concern in this thread.
 

Picard

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I'm not an aviation or military historian so i can't comment on the Vietnam air battles.
But in that era MiG-21 was a formidable interceptor & US pilots might have suffered from overconfidence.
It was also smaller and more agile.

It seems to contradict the screenshot which i shared where inside the exhaust a ring of concentrated heat is seen which would be this outer channel which u say. A cooling channel of air cannot glow hottest.
If there is really a cooling channel then it seems France is keeping the better engines for their domestic jets, not for exported ones.
Wrong. The cooling channel, if I am correct about it, would be between the nozzles.

Still, even if there is not a cooling channel for the nozzles, fact is that M88-2 has double cooling channel for the engine body where most jets have only one.

At high altitude bcoz the air temp. drops, an uncooled jet would be more porminent, hence the comprehensive cooling required. Otherwise so many diagrams from R&D sites, so many scientists & engineers working & already implemented equipment is waste of tax payer's money & hence all 6th gen development should also be stopped then. But this is not the pinnacle of mil. aviation, it is just the starting. A better Sword & then a better Shield are alternate aspects of repeatitive developments.
Rafale has Hot Spot treatment, which as name suggests is designed to reduce Rafale's hot spots. But I do not know what exactly it entails.

May be a futuristic engine will have distributed apertures like F-117 or Harrier's Rolls Royce engine but also with afterburning & supercruise capability.
I am not certain F-117 engine setup is viable for fighter jets, but I guess we'll see.

Shrouded nozzle (w/o comprehensive cooling) is a small, cheap, common add-on till 4th gen jets, not sufficient beyond that.
From where enemy will be detected or not detected is not known hence only frontal aspect cannot be relied upon. Bcoz the inner nozzleis always hot even at low speeds & non-afterburning level, that's all the outer nozzle takes care of.
There is literally no aircraft that can eliminate inner nozzle signature. Even F-22 still has visible inner nozzle, though in F-22's case it is square due to TVC requirements and somewhat shrouded.

I mentioned briefly in a generic way that the idea of comprehensive cooling is part of stealth/5th gen jet design. 4th gen jets don't have additional space required for additional equipement.
Majority of said "additional space" in 5th generation jets is taken up by internal weapons. So I fail to see why would they have any more space for cooling equipment than earlier aircraft.

But same % level of 2 engines are not same.
M88 100% dry thrust is 50KN
F-135 100% dry thrust is 125KN
AL-41F 100% dry thrust is 87KN
All engines have different dimensions, weight, compression stages, combustion chambers, nozzles, additional teachniques. Hence there is no global ISO standard to measure & rank engine design.
So throttle setting cannot be a measure of overall jet's performance.
Anyways this is not relevant to my original post or concern in this thread.
It is relevant, in fact, it is the key when it comes to IR signature of a jet. And again, what matters are not so much total values, but rather percentages.

Rafale at 100% dry thrust goes at Mach 1,4. Normal cruising speed of Mach 0,9 is achievable at 50% dry thrust IIRC.

F-35 at 100% dry thrust goes at Mach 1,2 at most. In fact, it is said that it can maintain Mach 1,2 for a dash of 150 miles, but it is never explained why 150 mile limit. Most likely is that it requires use of low afterburner for that, so not a true supercruise.

Su-35 at 100% dry thrust goes is also claimed to be capable of supercruise. But again, no mention of speed. It is however likely marginal - no more than Mach 1,1.

So as you can see, despite Rafale having the weakest engines, fact that it is also the lightest of the three allows it to achieve highest kinematic performance out of the three aircraft being compared. And this translates into lowest IR signature in operational terms, as it does not need to use afterburners as often.
 

Bhartiya Sainik

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Just bcoz our country has imported a product doesn't mean we'll brag, boast, blindly support every aspect of it without rectification. We need to act like a smart customer rather than prey to marketing agents.
Marketing tactics are applicable in every business, commercial or military.

Wrong. The cooling channel, if I am correct about it, would be between the nozzles.
Still, even if there is not a cooling channel for the nozzles, fact is that M88-2 has double cooling channel for the engine body where most jets have only one.
:facepalm: :doh::frusty:
U r going in circles. Don't stubbornly assert "wrong" for other person if U use 'IF' & 'WOULD' for urself to be correct. Others can be wrong only when u r 101% correct with facts VERIFIABLE anytime, anywhere.
U confused b/w core area blade cooling & bypass channel. Please use the right terms for engine parts.
Blade cooling is applied at center of engine & nozzle is at aft end, u r mixing the 2 things.
In a simple diagram where is the compressor blade? Where is turbine blade? Where is bypass channel? Where is nozzle? U mixed up everything.
1650040672289.png

Whatever u say, please use diagram or pic, edit it in MSpaint, etc & show to members exactly where is your percieved nozzle, channel, etc. otherwise we all will be going in circles everyday endlessly. Importers like U n me will gain nothing but the exporter will enjoy the show & make money.
If u claim that M88-2 has double channel cooling then it has to be something similar to 1st graphic i shared, but the M88 diagram is no way near this.
1650042321397.png


But what u r talking about could be the M88-4E improved version, not M88-2 in service at this time.

1650051134139.png

But "Indian" Rafales don't seem to have any cooling channel at all, not even 1 perhaps, bcoz cooled channel doesn't glow hot with strinking contrast.
1650042678208.png

I would be so happy if someone can point out the cooling channel in real life pic but i think France gave us obsolete engines & kept the newer ones for itself.

I traced ur French labeled diagram to websites like ********** where some member shared an edited pic of EJ-200 engine & writing "M88= dual cooling channel", here is the problem, that member used the combustion chamber exit channel having the primary hottest air as 2nd cooling channel :doh::daru::frusty: starting a chain reaction of wrong references & misconceptions. Later it becomes a marketting gimmick.
People are misinterpreting the parts of engine & mixing cooling of various external & internal parts for different purposes. :smash::scared2::crying:


1650034530178.png


The other image which u shared is actually focussed on the afterburner chamber body (not nozzle) made of kevlar composite to reduce engine body heating, not related to plume. So again France might be testing a newer engine version & keeping it for itself, not export.
1650047387904.png


Rafale has Hot Spot treatment, which as name suggests is designed to reduce Rafale's hot spots. But I do not know what exactly it entails.
That hotspot or airframe treatment is done by replacing metal based skin with composite skin. But engines will get stronger with each gen. 6th gen will require DEW means more power required, means more heat & it also depends on band of sensor is tuned to - LWIR, MWIR, SWIR. Hence additionally if any jet can give HX treatments then even better.
But will the exported variants will have the composite body or metal body is also a question.


I am not certain F-117 engine setup is viable for fighter jets, but I guess we'll see.
Today's jet engine was science fiction in WW era so we may have breakthroughs within few decades, perhaps for 7th gen jets, i don't think i will be alive for it, but perhaps i might see the theory if i survive to 70s or 80s senilty age. For now we only have some briefly imagined art.

1650045018285.png

F-117 exhaust was static with no moving parts or afterburner. It simply spread the exhaust over cooling tiles.
Harrier engine had 4 swivelling nozzels but w/o afterburner or IR treatment.
So next logical step is to combine features to have mechanically morphing multi-aperture nozzles which can be individually controlled.

There is literally no aircraft that can eliminate inner nozzle signature. Even F-22 still has visible inner nozzle, though in F-22's case it is square due to TVC requirements and somewhat shrouded.
Inner nozzle signature is not supposed to be "eliminated" but "shielded" bcoz it provides the spine of thrust.
F-22's engine & nozzle & airframe are still mystery. I'm not fully confirmed what technique they are applying but the costliest jet who's export is prohibited must be hiding secrets.
The nozzle appears to be very strong & sturdy.
F-22 nozzle at AF museum.jpg


At 100% mil-power the nozzles close so much it looks like platipus 😑
1650052983960.png


The side walls of nozzles have mysterious gaps which could be for cooled air. The nozzle has tiny perforated holes which could also be for cooled air. YF-23 also has it. Lastly, we can see that there is a radial frill like structure which could be angular cooled vanes blocking the gas exit chamber, this is there in F-35 too.

1650077286759.png


Majority of said "additional space" in 5th generation jets is taken up by internal weapons. So I fail to see why would they have any more space for cooling equipment than earlier aircraft.
Common citizens like u n me would obviously fail to understand something which is not our qualification & profession. There is some technique called "Vapor Compression Refrigeration" (https://en.wikipedia.org/wiki/Vapor-compression_refrigeration) which might be used in some jets. it is proposed for our AMCA also.
In 5th gen jets focus on internal weapons gives way for overall inflation of airframe which can be used for extra equipments, sensors, fuel.


It is relevant, in fact, it is the key when it comes to IR signature of a jet. And again, what matters are not so much total values, but rather percentages.
Rafale at 100% dry thrust goes at Mach 1,4. Normal cruising speed of Mach 0,9 is achievable at 50% dry thrust IIRC.
F-35 at 100% dry thrust goes at Mach 1,2 at most. In fact, it is said that it can maintain Mach 1,2 for a dash of 150 miles, but it is never explained why 150 mile limit. Most likely is that it requires use of low afterburner for that, so not a true supercruise.
Su-35 at 100% dry thrust goes is also claimed to be capable of supercruise. But again, no mention of speed. It is however likely marginal - no more than Mach 1,1.
So as you can see, despite Rafale having the weakest engines, fact that it is also the lightest of the three allows it to achieve highest kinematic performance out of the three aircraft being compared. And this translates into lowest IR signature in operational terms, as it does not need to use afterburners as often.
No technical paper or person talk in terms of % thrust but in terms of international units & metrics.
IRS is never measured or mentioned in terms of throttle power which is just a mechanical operation.
When we go to fuel station we don't show the fuel meter & tell to fill 50% or 30% tank bcoz each vehicle has differnt tank capacity, we have to specify fuel required in liters/gallons.
There are variants of M88 engines also so tomorrow M88-3 will give 80-90KN increasing performance, same with other jets also.
How much Mach # will a jet achieve & under what load of fuel & weapons is just trial & error method, also depends on altitude. And like i said the airframe design also different.
U can imagine a modified Rafale with CFT & IWB also then at same previous throttle % its drag, empty & gross weight will increase, & lift, T/W ratio, speed, range will decrease. To compensate u willrequire a better engine.
Another simple real example - GE-414 engine is used in F-18 & Grippen & also will be used in our MWF, TEDBF, AMCA. But all 5 jets are different, 1or 2 engine, delta-canard or tandem bi-plane, 4th or 5th gen, light or medium weight. Hence they will have different performance in agility, speed, range, etc. So even with the same engine there is no global or national agreement & benchmarking on aircraft design.
A delta-canard would be different from tandem bi-plane. Center of gravity & center of lift would be different, affecting lift, drag & speed. If u give canards to bi-plane & make it tandem tri-plane like Su-30MKI or F-15 SMTD/VISTA then additional lift would allow some more load.
When a product is made it has a lot of goals & objectives, primary & secondary. If every aspect has to be made superior then the product cost would be very high & unbearable. It would be technologically possible but practically not feasible.
Rafale C/M empty weight is 9.9/10.6 tons, F-35A/C is 13.3/15.7 tons, Su-35 is 19 tons.
You won't see Su-3X carrying fuel tanks as they can carry 11 tons fuel & F-35 carries 9 tons but Rafale carries 4.7 tons internally hence need to carry 2-3 extarnal ones depending upon mission.
MTOW of Rafale is 24.5 tons, of F-35 is 31.8 tons (int.+ext.), of Su-35 is 34.5 to 38.8 tons.
F-22 empty is 19.7 tons, fuel 8.2 tons, MTOW 38 tons, 116KN of dry thrust giving M1.8 super-cruise, top speed M2.3
EF-2000 the closest design to Rafale, empty 11 tons, fuel 5 tons, MTOW 23.5 tons, 60KN dry thrust gives M1.5 super-cruise. It appears to be slightly better.
Rafale will loose most gunfights against TVC jets like F-22, Su-35.
Some people might also consider unfair to compare single & dual engine jet which requires more servicing & cost than 1 engine.
Someone can say that Rafale takes 2 engines to be better than F-35. if it was 1 engine like JAS-39 Grippen then it would be different narrative. We are making 2 medium weight jets - MWF with 1 engine & TEDBF with 2 engines. It would be so intresting to see their protoypes.
So all products have plus/minus points & different goals & objectives.
Hence 4th & 5th gen jets cannot be compared straight bcoz 4th gen jets are slimmer while 5th gen are bulkier. So among 4th gen a full load can be considered but among stealth jets only internal load is considered otherwise no stealth benefit.

U hate F-35 in every way that's visible but it got a big but strongest engine due to VTOL requirement. I already said that if it was a dual engine jet like J-31/35 or AMCA then it would have an improved version of F-22's engine with TVC, in which case it would be superior to all dual engine medium weight jets.
U love Rafale, we also like it, it is a great jet among 4th gen, but don't sing about it so much as if it is pinnacle & benchmark of mil-aviation & end of line. It will be replaced by FCAS.
 

Picard

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U r going in circles. Don't stubbornly assert "wrong" for other person if U use 'IF' & 'WOULD' for urself to be correct. Others can be wrong only when u r 101% correct with facts VERIFIABLE anytime, anywhere.
This is what you said:
It seems to contradict the screenshot which i shared where inside the exhaust a ring of concentrated heat is seen which would be this outer channel which u say. A cooling channel of air cannot glow hottest.
I have, from the start, said that if there is a second cooling channel then its exhaust is between the nozzles. It is outer nozzle's purpose to shield inner nozzle from observation, so best way to reduce IR signature is to help isolate outer nozzle from engine exhaust and inner nozzle itself.

Ergo, your statement is wrong.

Whatever u say, please use diagram or pic, edit it in MSpaint, etc & show to members exactly where is your percieved nozzle, channel, etc. otherwise we all will be going in circles everyday endlessly. Importers like U n me will gain nothing but the exporter will enjoy the show & make money.
If u claim that M88-2 has double channel cooling then it has to be something similar to 1st graphic i shared, but the M88 diagram is no way near this.
Compare F110 and M88-2: especially how narrow is the space between inner and outer skin for F110 and wide for M88-2:
F110GasTurbine - Copy.gif

m882 - Copy.gif

It seems M88-2 might have additional layer of skin wrapping around the turbine itself compared to F110, but I am not quite certain on that.

Also, can you write normal English? You are rather difficult to understand this way.

But "Indian" Rafales don't seem to have any cooling channel at all, not even 1 perhaps, bcoz cooled channel doesn't glow hot with strinking contrast.
If there is a cooling channel, its exhaust is between the nozzles, not within the inner nozzle...

The other image which u shared is actually focussed on the afterburner chamber body (not nozzle) made of kevlar composite to reduce engine body heating, not related to plume. So again France might be testing a newer engine version & keeping it for itself, not export.
Reduced engine body heating was precisely part of my point, because it means that it reduces heating of the aft portion of the airframe.

Second important part of the image is how there is a significant distance between the engine plume and the outer nozzle, which means that outer nozzle will be much cooler than would be the case in your typical jet engine where said nozzle actually "hugs" the inner nozzle and the exhaust plume. And, as I have already pointed out, outer nozzle shields the hottest part of the plume from view from frontal aspect.

But will the exported variants will have the composite body or metal body is also a question.
Why would they have metal body? That would just mean creating a completely different production line for what?

At worst, they may not receive RAM absorbent paint/coating that French Rafales have...

Inner nozzle signature is not supposed to be "eliminated" but "shielded" bcoz it provides the spine of thrust.
F-22's engine & nozzle & airframe are still mystery. I'm not fully confirmed what technique they are applying but the costliest jet who's export is prohibited must be hiding secrets.
The nozzle appears to be very strong & sturdy.
The side walls of nozzles have mysterious gaps which could be for cooled air. The nozzle has tiny perforated holes which could also be for cooled air. YF-23 also has it. Lastly, we can see that there is a radial frill like structure which could be angular cooled vanes blocking the gas exit chamber, this is there in F-35 too.
Possibly. I imagine these vanes have exhaust of air which helps shield aircraft body from the exhaust plume.

Issue with square nozzle is that it also makes thrust less efficient, so you need more thrust for the same performance.

Common citizens like u n me would obviously fail to understand something which is not our qualification & profession. There is some technique called "Vapor Compression Refrigeration" (https://en.wikipedia.org/wiki/Vapor-compression_refrigeration) which might be used in some jets. it is proposed for our AMCA also.
That "technique" is literally what is used in your home fridge. Also, I believe it is mostly used to cool down electronics, not engines.

No technical paper or person talk in terms of % thrust but in terms of international units & metrics.
Irrelevant. I talk in thrust percentages because thrust percentages are what matter here.

Rafale will loose most gunfights against TVC jets like F-22, Su-35.
Riiight... Thrust vectoring is not a magical "I win" button, and it cannot fully compensate for weight and aerodynamic disadvantage. In fact, it is merely a way to make heavy aircraft competitive with their much smaller counterparts, but it does not allow them to magically beat the opponents that are smaller, lighter, have superior aerodynamics and are consequently more agile.

In fact, Rafale beat F-22 in a mock dogfight. Now, the outcome itself is not that important; what is important is that Rafale had held advantage throughout, despite F-22s thrust vectoring:

What thrust vectoring does is improve nose pointing ability. However, there are two issues here:
1) it comes with massive disadvantages
2) close-coupled canards give most of the same benefits

Aircraft with thrust vectoring can point nose more quickly, which allows it to initiate turn more quickly - but maximum turn rate is still dependant on lift / wing loading. It also can improve roll onset and rate of roll while in turn as control surfaces do not need to be used to maintain the turn. Major disadvantage is that the axis of thrust no longer corresponds to either axis of the aircraft or vector of movement, thus leading to massive energy loss.

Close coupled canards provide most of the same benefits, albeit in a significantly different manner. What canards do is that they - similar to LERX - create vortices, thus energizing air flow over the wing. This has two major benefits. By delaying the separation of air (stall) to a higher angle of attack, maximum lift and thus turn rate is improved. But energized airflow also means that control surface input becomes more effective, and remains effective to a higher angle of attack. This results in improved pitch onset, roll onset and roll rates, as well as higher controllable angle of attack.

U love Rafale, we also like it, it is a great jet among 4th gen, but don't sing about it so much as if it is pinnacle & benchmark of mil-aviation & end of line. It will be replaced by FCAS.
Which doesn't mean FCAS will be better than Rafale. But it is still in the future, so we will see.
 

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Rafale is versitile jet have very balanced firepower for air to air and air to land mission capability suits India very well


Hard to understand IAF needed 114 and ordered 36


 

Bhartiya Sainik

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This is what you said:
I have, from the start, said that if there is a second cooling channel then its exhaust is between the nozzles. It is outer nozzle's purpose to shield inner nozzle from observation, so best way to reduce IR signature is to help isolate outer nozzle from engine exhaust and inner nozzle itself.
Ergo, your statement is wrong.
Yeah so what I said through a real life pic of "Indian" Rafale is not convincing to have cooling channel. U could have provided pic of French Rafale to clarify which u have not till now.
Just having an outer nozzle or cover or shroud is 1 thing which many 4th gen jets have & having a cooled air pass through it is another thing.
I don't hav any ego, i'm talking on basis of whatever info i can find & trying to correlate the theory with implementation.

Compare F110 and M88-2: especially how narrow is the space between inner and outer skin for F110 and wide for M88-2:
View attachment 151099
View attachment 151100
It seems M88-2 might have additional layer of skin wrapping around the turbine itself compared to F110, but I am not quite certain on that.
So this is what i already showed that in M88-2 diagram the cooling channel open within inner nozzle, not in space b/w inner & outer nozzle where the actuator assemblies block the gap.
Skin wrapping around turbine??? U mean blisk or channel wall?
In M88-2 i doubt but in M88-3/4/4E, etc many improvements might have been done. The question is do we have public picture of the improved engines & if exported or not.
From diagram I really doubt if F110 has a bypass cooling channel bcoz that would make the skin very thin & endanger structural integrity.

If there is a cooling channel, its exhaust is between the nozzles, not within the inner nozzle...
:frusty::crying::mad2:
This statement is exactly the problem & in contradiction with pictures available, bcoz b/w the nozzles the actuator assemblies block the space.

Second important part of the image is how there is a significant distance between the engine plume and the outer nozzle, which means that outer nozzle will be much cooler than would be the case in your typical jet engine where said nozzle actually "hugs" the inner nozzle and the exhaust plume. And, as I have already pointed out, outer nozzle shields the hottest part of the plume from view from frontal aspect.
This was already understood & not the concern.
While the M88 team decided to leave the gap wide open, many other nozzle makers decided to converge the trailing edges of panels. That doesn't mean the inner panels will transfer all heat by conduction to outer panels. The M88 outer panels are made of ceramic composites so the other makers might have done same/similar thing too. Otherwise everybody would be making same type of gap-nozzles.


Why would they have metal body? That would just mean creating a completely different production line for what?
At worst, they may not receive RAM absorbent paint/coating that French Rafales have...
So that's why i said that it is a question, i'm not sure abt it. Separate production line is required depends on ordered numbers, size of fuselage parts, export policy, technology transfer policy, assembly techniques, etc. But looking at high cost of Rafale i think that it will have same composite body.
But still in general the export models are inferior than domestic models in many H/w & S/w aspects so that the customer will be dependant on maker for decades. If licensed production is awarded still many things have to be imported.
RAM is not the only prohibitted thing. I wonder since when Rafale got RAM. These days every OEM is claiming to have RAM that too on 4th gen jets making 5th gen airframe design considerations look as foolish & wastage. Rafale's composite material helps to reduce RCS but RAM paint?


Possibly. I imagine these vanes have exhaust of air which helps shield aircraft body from the exhaust plume.
Issue with square nozzle is that it also makes thrust less efficient, so you need more thrust for the same performance.
Same function of a cooling channel except the nozzle shape is different.
Yes, as per concepts of fluid dynamics the rectangular nozzles loose some efficiency but it seems the makers are ok with it. Many UCAVs also have it. Future may see some intermediate shape like hexagon.

That "technique" is literally what is used in your home fridge. Also, I believe it is mostly used to cool down electronics, not engines.
In my 1st reply itself I already showed u block diagram of series of types of HX still after some discussion u said u fail to understand why spend extra space for more cooling & now also u believe not for jet engines.
U wanna believe & advocate M88's dual channel cooling but ended up mixing blade cooling & nozzle, but u could hav done a simple google search on what i mentioned abt extended comprehensive cooling.
It has been proposed for our AMCA & similar system used on F-22/35 & perhaps on other 5th gen jets too like Su-57, J-20/35, KFX, etc.
Generation of design data for
Condenser of Vapour Compression Module (VCM) of AMCA”.


It must be part of detailed design phase.
Seems like AMCA will use
All Electric Environmental
Control System (AEECS) which works on Vapor Compression Refrigeration System.
1650140664608.png

The system is called ECS (EnvironmentalControl System) or TMS (Thermal Managament System). You can google & find many papers on this.
Here is a screenshot from 24 years old document on F-22's ECS/TMS from 1998 mentioning Vapor Cycle System.
1650140370501.png


Here are some screenshots from PPT file of F-35by google search

1650141520275.png

1650141546417.png

1650141576448.png

1650141601930.png


Item 210, 218, 221 are 3 type of HX.
A 4th HX is fan duct HX
1650141953066.png


A 5th HX is Fuel-air HX on top side of right engine intake with small inlet.
1650160121610.png


A 6th HX is somewere near cockpit for HVAC & avionics.



Irrelevant. I talk in thrust percentages because thrust percentages are what matter here.
SI & Imperial units used by every industry including Dassault, Snecma, DGA are irrelevant to you? So u will go to fuel station & tell bluntly to fill 30% fuel in your vehicle? :doh: :daru::hail::clap2:
There are some self-service fuel stations also, what entry do u do with keypad? fuel % or liters/gallons? 🙄🤔


Riiight... Thrust vectoring is not a magical "I win" button, and it cannot fully compensate for weight and aerodynamic disadvantage. In fact, it is merely a way to make heavy aircraft competitive with their much smaller counterparts, but it does not allow them to magically beat the opponents that are smaller, lighter, have superior aerodynamics and are consequently more agile.

In fact, Rafale beat F-22 in a mock dogfight. Now, the outcome itself is not that important; what is important is that Rafale had held advantage throughout, despite F-22s thrust vectoring:

What thrust vectoring does is improve nose pointing ability. However, there are two issues here:
1) it comes with massive disadvantages
2) close-coupled canards give most of the same benefits

Aircraft with thrust vectoring can point nose more quickly, which allows it to initiate turn more quickly - but maximum turn rate is still dependant on lift / wing loading. It also can improve roll onset and rate of roll while in turn as control surfaces do not need to be used to maintain the turn. Major disadvantage is that the axis of thrust no longer corresponds to either axis of the aircraft or vector of movement, thus leading to massive energy loss.

Close coupled canards provide most of the same benefits, albeit in a significantly different manner. What canards do is that they - similar to LERX - create vortices, thus energizing air flow over the wing. This has two major benefits. By delaying the separation of air (stall) to a higher angle of attack, maximum lift and thus turn rate is improved. But energized airflow also means that control surface input becomes more effective, and remains effective to a higher angle of attack. This results in improved pitch onset, roll onset and roll rates, as well as higher controllable angle of attack.
Seems to be ur personal blog site.
The ATF & Rafale programs were developed in 1980s, ATF after Rafale obviously, so both were aware of eachother. ATF team during design & from YF-22 to F-22 had inputs from experiments like F-15-SMTD/VISTA, F-16 MATV/AFTI, F-18 HARV, X-31, etc & some ATF protypes did have canards but ultimately cancelled due to stealth concerns.
I personally watched Rafale's impressive performace in Aero-India 2013 at Yelahanka AFB near Bangalore.
I mentioned the F-22-Rafale dogfight exercise long back in other threads & websites also. I even said that our IAF Rafales will defeat all Pak & Chinese jets, but J-10C is a concern as it got TVC+canards.
But we don't know how many dogfights took place & how many each side won. F-22 HUD videos were not published. There were speculations by both sides. We don't even know the skill & experience level of pilots involved. What was the load on both jets?
In video the Rafale pilot was screaming for breath as if he was given ultimatum to score at least 1 gun kill for publicity. Rafale repeatedly got "RELEASE STICK" & "RECOVER" messages to avoid stall or recovering from it while F-22 is a stall free jet due to TVC & T/W ratio always >1. The dogfight took place in cloudy weather which is dangerous for jets without 360 degree sensor fusion. F-22 has 360 degree EO & RF coverage, Rafale doesn't & in video it was losing lock.
It is definitely natural for canards positioned at front to control the pointing of a jet very well, simple physics, but not suited to stealth jet. What Chinese did with J-20 got lot of criticisms & their performance videos were not very impressive on agility.
Secondly a smaller jet's turning radius will be smaller than a bigger jet.
But Rafale cannot achieve 70 degree AoA but F-22 has displayed it publicly. If TVC jets got T/W ratio >1 & good avionics then they can dance on their nozzles or remain almost still. But a canard jet has to struggle so much to score a kill with its pilot sweating & screaming for breath & body under pain by G-suit squeezing by trying to take tight turns. TVC gets rid of such repeated painful sweaty effort.
If F-22 being bigger & heavy loses energy then from beginning itself it had plans for a stronger engine obviously.
Rafale empty 9.9T+ full fuel 4.7T+6 AAMs 1.3T=15.9T=35,000lbs. M88-2 has 50KN dry & 75KN ABthrust. AB-T/W ratio = 0.96
With all missiles used & 50% fuel, 9.9T+2.3T=12.2T=26,840lbs. AB-T/W ratio=1.25
So obviously the ATF team pushed for strong engines. F-119-PW100 has 116KN dry thust, 156KN AB thrust/eng. Empty 19.7T+ full fuel 8.2T + 6 AAMs 1.3T=29.2T=64,240lbs. AB-T/W ratio = 1.1
With all missiles used & 50% fuel, 19.7+4.1=23.8T=52,360lbs. AB-T/W ratio=1.33
So both sides will score kills but at this time my take is still that Rafale will loose more than 50% gunfights against F-22.
When we see Su-35 & Su-57 their videos show better performace than F-22. While Su-57 is the only tandem tri-plane with Levcons whichmakes it perhaps most dangerous gunfighter, Su-35 removed canards & still retained its agility. My take is that F-22 might win a BVR but will loose a gunfight against them more than 50% of times. Others may disagree.
So Rafale facing these 2 Sukhois would be even worse.
And if M88 has better versions then other engine makers might have worked on their better versions too.
BUT, if F5/6 MLU gives TVC & more thrust to Rafale then it can emerge as unbeatable champion. And future will have UCAVs free from human G tolerance constraints so Rafale better have a TVC upgrade with better engine.


Which doesn't mean FCAS will be better than Rafale. But it is still in the future, so we will see.
All 6th gen have to be better otherwise it is wastage of tax payer's money. The makers still have time to think. When we are talking abt a gen leap then we hav to make a better jet, simple. 6th gen is expected to have DEW to eliminate gun-fight. When sufficient KW laser pods have been tested on AH-64 & perhaps legacy jets then there is no doubt that 6th gen can mount a flat laser turret like a DIRCM.
Apache with laser pod & F-35 concept with DEW.jpg

Through sensor fused avionics the IRST/OLS/OSF/EOTS maintains a stable lock on target. Hence a shot from DEW will not only accurately damage the target's airframe but also the canopy & pilot from some angles. Human cannot sustain such laser damage & hence trying to score a gun kill would be futile. If 2 pairs of DEW turrets are mounted, 2 forward, 2 backward then minimum 2 to all 4 at certain angles can fire at a target, be it a missile or a jet. That's the endgame advantage of gen leap. Only UCAVs have a chance to fight a DEW jet.
 

Picard

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So this is what i already showed that in M88-2 diagram the cooling channel open within inner nozzle, not in space b/w inner & outer nozzle where the actuator assemblies block the gap.
Skin wrapping around turbine??? U mean blisk or channel wall?
In M88-2 i doubt but in M88-3/4/4E, etc many improvements might have been done. The question is do we have public picture of the improved engines & if exported or not.
From diagram I really doubt if F110 has a bypass cooling channel bcoz that would make the skin very thin & endanger structural integrity.
I meant the channel wall.

This statement is exactly the problem & in contradiction with pictures available, bcoz b/w the nozzles the actuator assemblies block the space.
Why would that be a problem?

This was already understood & not the concern.
While the M88 team decided to leave the gap wide open, many other nozzle makers decided to converge the trailing edges of panels. That doesn't mean the inner panels will transfer all heat by conduction to outer panels. The M88 outer panels are made of ceramic composites so the other makers might have done same/similar thing too. Otherwise everybody would be making same type of gap-nozzles.
Problem with converging panels is not that panels themselves will heat up, but rather that plume is visible from increased range of angles.

So that's why i said that it is a question, i'm not sure abt it. Separate production line is required depends on ordered numbers, size of fuselage parts, export policy, technology transfer policy, assembly techniques, etc. But looking at high cost of Rafale i think that it will have same composite body.
But still in general the export models are inferior than domestic models in many H/w & S/w aspects so that the customer will be dependant on maker for decades. If licensed production is awarded still many things have to be imported.
RAM is not the only prohibitted thing. I wonder since when Rafale got RAM. These days every OEM is claiming to have RAM that too on 4th gen jets making 5th gen airframe design considerations look as foolish & wastage. Rafale's composite material helps to reduce RCS but RAM paint?
Rafale was said to have RAM paint even back in 1995:
2022-04-17 (6) - Copy.png


The system is called ECS (EnvironmentalControl System) or TMS (Thermal Managament System). You can google & find many papers on this.
Here is a screenshot from 24 years old document on F-22's ECS/TMS from 1998 mentioning Vapor Cycle System.
OK, thanks.

SI & Imperial units used by every industry including Dassault, Snecma, DGA are irrelevant to you? So u will go to fuel station & tell bluntly to fill 30% fuel in your vehicle? :doh: :daru::hail::clap2:
You know, thinking about what is being written would not be amiss. You use smileys, yet while I have made mistakes, you have shown yourself to be incapable of understanding basic concepts time and again.

Total values do not matter in what I had written because we are talking about comparative performances. Lighter fighter will have less thrust, but can easily have far better acceleration and cruise speed performance. Why? If it has higher thrust-to-drag ratio, it will accelerate more quickly; if it has higher thrust-to-weight ratio, it will have better vertical maneuverability; if it has higher lift-to-drag ratio, it will be able to retain energy better; if it has higher lift-to-weight ratio, it will turn more quickly.

The ATF & Rafale programs were developed in 1980s, ATF after Rafale obviously, so both were aware of eachother. ATF team during design & from YF-22 to F-22 had inputs from experiments like F-15-SMTD/VISTA, F-16 MATV/AFTI, F-18 HARV, X-31, etc & some ATF protypes did have canards but ultimately cancelled due to stealth concerns.
Precisely. Which is why F-22 has thrust vectoring instead.

But we don't know how many dogfights took place & how many each side won. F-22 HUD videos were not published. There were speculations by both sides. We don't even know the skill & experience level of pilots involved. What was the load on both jets?
And again, outcome itself doesn't matter as much. What matters is performance shown by Rafale, which shows that it doesn't really need thrust vectoring, as it is able to fight and retain advantage in slow-speed regime where thrust vectoring shines.

In video the Rafale pilot was screaming for breath as if he was given ultimatum to score at least 1 gun kill for publicity. Rafale repeatedly got "RELEASE STICK" & "RECOVER" messages to avoid stall or recovering from it while F-22 is a stall free jet due to TVC & T/W ratio always >1. The dogfight took place in cloudy weather which is dangerous for jets without 360 degree sensor fusion. F-22 has 360 degree EO & RF coverage, Rafale doesn't & in video it was losing lock.
He was not "screaming for breath"; these "screams" are actually grunts whose purpose is to help pilot cope with G-forces involved in hard maneuvers. F-22 pilot will have been screaming just as much.

"Release stick" and "recover" are warnings due to loss of airspeed due to hard maneuvers. Any aircraft will stall out if it loses lift - F-22 is not "stall free", what kind of fantasy were you reading? Do you even know what stall is? Post-stall maneuverability does not mean stall free.

Lock is usually maintained with radar, and hard maneuvers can cause radar to lose lock. Radar also needs several seconds to establish lock. Nothing surprising there.

F-22 and Rafale both have 360 degree sensor coverage. F-22 has EO (specifically, UV) missile warning system, while Rafale has IR DDM-NG MAWS, which also has 360 degree coverage. So no difference there, except F-22s system might have longer range while Rafale's would be better at detecting coasting missiles. And yes, it would also be better at targeting aircraft, assuming it receives upgrades necessary for that.

It is definitely natural for canards positioned at front to control the pointing of a jet very well, simple physics, but not suited to stealth jet. What Chinese did with J-20 got lot of criticisms & their performance videos were not very impressive on agility.
Secondly a smaller jet's turning radius will be smaller than a bigger jet.
Not all canards are equal. J-20 uses long coupled canards, which are merely a control surface - forward positioned tail, essentially. In aerodynamics terms, J-20 is quite conventional. J-20 itself is also very large and heavy aircraft, which is additional minus.

What Rafale has are close coupled canards, which have absolutely nothing to do with J-20's long arm canards. I had written on close-coupled canards before, and you have list of literature at the end of the post. Read it.

Or if you do not want to, I found a few documents. Excerpts are below, but long story short:
1) close coupled canard delays stall onset, thus allowing higher maximum lift and improved lift-to-drag ratio at high angles of attack
2) close coupled canard delays vortex bursting (leading to above) best when it is close in front and above the wing; coplanar canard is much less effective, as is canard positioned far in front of the wing
3) due to the above, close-coupled canard above the wing produces lift-to-drag ratio some 12% better than a coplanar canard
4) in general, close-coupled canard improves both maximum lift and lift-to-drag ratio compared to either wing-only, wing-tail or other types of wing-canard configurations (e.g. long moment arm, close-coupled coplanar etc.)

At low angle of attack (AoA) area (below 20°) the value of Cl for each model has a similar value. After the AoA is higher than 20° , then begin to happen the differencecoefficient value of lifting force. In the model aircraft without using canard, the value of Cl increased up to the angleof attack 35° and after that decreased the value. This result has a good similarity compared to the experimental results using a water tunnel. In the configuration with the addition of canard, the lift coefficient still increases until the maximum AoA isabove 40° . The increase of maximum AoA in the canard configuration indicates that at an angle higher than 35° there is still additional lifting force and not stall yet. Almost all canard configuration configurations used can delay the occurrence of stall, but in detail, there are differences in the characteristics of Cl values for each configuration.
The results showed that the addition of canard would be able to increase the lifting force coefficient up to 5 - 12.1 %. The canard position on the main wing affects to the vortex flow interaction, the value of lift coefficient, andmaximum angle of attack. In the canard position on the upper side and adjacent to the main wing gives the best value against the maximum Cl value shift between 5 - 10 degrees which indicates a stall delay in the aircraft model
Recently, projected fighter aircraft designs such as the Saab JAS39 Gripen, the U.K. ACA, the French ACX, and the IAI Lavi use a variation of the canard surface in a "close-coupled" arrangement. The foreplane is close coupled when it is placed a relatively short distance ahead and slightly above the main wing such that the wake (vortices) shed from the lifting canard reenergize the flow over the inner portions of the wing. This tends to suppress vortex bursting, thereby promoting more linear lift and pitching moments to high AOA beyond the nominal CL . In particular, the delta wing planform max which offers lower wave drag over a wide range of Mach numbers can benefit from the canard by providing better lift distributing (higher LID) in transonic flow conditions and increased usable lift in takeoff and landing.
A comparison of Figures 26 and 19 shows a dramatic difference in the flowfield due to the addition of the canard to the model. Figure 26(a) shows two regions of unobtainable data, one at approximately (5,2) and the other very near the wing leading edge at about (0.5,3.5). The area located near (5,2) was the canard leading-edge vortex which had moved downstream from grid 1. The area near (0.5,3.5) could have been the result of two possible phenomena. One is that the large region of chaotic flow seen in Figure 19 had been forced into a small "pocket" of separated reversed flow. The second is that the wing leading-edge vortex had reformed due to the presence of the canard vortex. The flow visualization in Figure 27 indicates the presence of a wing leading-edge vortex. Furthermore, the pattern formed by the streamlines in Figure 26(b) indicates that rather than the flow having merely been forced into a "separation-pocket", the leading-edge vortex was actually energized by the canard vortex and had reformed. The flow visualization suggests that a strong vortex has formed along the wing surface.

The energizing of the wing leading-edge vortex in this manner and the reattached flow over the inboard wing section would lead tc a level of enhanced lift which would be greater than that obtained by simply adding the lifting surface of the canard. In fact, as was mentioned earlier, this was found to be exactly the case in previous studies [Ref. 2,3]. The mechanism is clearly demonstrated here. Also in Figure 26 can be seen a significant crossflow component between the canard vortex and the wing leading-edge vortex. In the vicinity of (2,1) the crossflow is as much as 65% of the total freestream velocity and approaches the wing perpendicular to its surface. The formation of oil parallel to the fuselage in Figure 27 could have been due, at least in part, to the stagnation of this large crossflow component on the wing surface.

The total-pressure-coefficient contours of Figure 28 show the presence of a third vortex not completely captured by the velocity-vector or velocity-streamline plots. Centered at (2.1,0.6), this vortex is believed to be the secondary vortex that had formed on the fuselage surface at grid 1. Most importantly, the contours of Figure 28 show that freestreamn total pressure extended to the wing surface over the inboard section. Clear evidence is provided that the flow had reattached over the inboard portion of the wing, enhancing significantly the lifting ability of the previously stalled wing.
These theoretical data seem to indicate that the canard and wing generate vortex lift when in the presence of each other. In some cases the leading-edge vortex-lift theory underpredicts the experimental CL,M - CL,C (figs. 15, 16 and 19); this result suggests the possibility that there may be tip-vortex lift effects (ref. 14). Further studies are required to understand the flow field produced by a close-coupled canardwing configuration.
1. In general, the effect of canard sweep on lift is small up to an angle of attack of 16°. However, for angles of attack greater than 16°, increasing the canard sweep results in an increase in lift developed by the canard for the canard above or in the wing chord plane. This increased lift results in a lift increase for the total configuration when the canard is above the wing chord plane. For the canard in the wing chord plane, the increased canard lift is partially lost by increased interference on the wing. 2. For the configurations with the canard in the wing chord plane, increasing the canard dihedral angle from -18.6° to 18.6° increased the maximum lift coefficient of the configuration. For the configurations with the canard above the wing chord plane, the highest maximum lift coefficient was developed when the canard had no dihedral. 3. In general, the configuration with the canards above the wing chord plane produced more linear pitching-moment curves throughout the angle-of-attack range than did the configuration with the canard in the wing chord plane. 4. The theoretical data would seem to indicate that the canard and wing generate vortex lift when in the presence of each other. 5. The effect of canard dihedral, for the canard in the wing chord plane, on the total Clp (partial derivative of rolling moment with respect to sideslip) for the configuration with the wing on, is small up to an angle of attack of approximately 8°; from 8° to approximately 20° the effect of canard dihedral on the total Clp is as expected (the higher the dihedral angle, the more negative the Cl1 ). However, above 22°, the configuration with the highest canard dihedral becomes the most unstable. The instability could be associated with the canard characteristics, wing interference characteristics, or the wing-alone characteristics. 6. The canard-wing configuration, with 60° swept canard, produced large unstable lateral-stability breaks
Overall, the addition of a canard will increase the lift coefficient of the aircraft model by up to 12%. In the low angle of attack (AoA) (under 20° ) the Cl value for each model has the same value. After AoA is higher than 20° , there is a difference in lift coefficient value. In aircraft models without using canard, the Cl value increases up to AoA 35° and after that decreases the value of Cl.
Figure 5 shows the difference in lift coefficient in detail at 30° -50° AoA for coplanar/horizontal and vertical canard position changes on the main wing. Figure 5a shows the difference in Cl values for coplanar/horizontal canard position. In the coplanar position, the canard position approaching the main wing (case A0) will produce the highest Cl value. This condition causes the AoA value at maximum Cl to shift at a higher angle of attack so that this configuration will be better able to maintain lift. Figure 5b shows the lift coefficient value in AoA detail with vertical canard position variation. It can be seen that from the parallel position to the main wing then shifts upwards causing a slight increase in lift. However, increasing position does not always increase Cl, in vertical distance configurations ½ tc and tc (cases A1 and A2) show the highest increase in Cl value, and after that, it decreases again.
In the case of changes in canard position horizontally (Cases A0, B0, C0, and D0) each has a different characteristic interaction between canard vortex and wing vortex. Figure 8 shows the formation of vortex core path-lines from the canard for the changes of horizontal canard position from the side and upper side views. The vortex core formed from the canard will interact with the main wing vortex core and became merge. In the canard position closest to the main wing, flow interactions occur faster and closer above the main wing. The farther canard position causes the vortex core trajectory to move upwards, the interaction decreases and the vortex core's merging location retreats to the main wing.

Similarly, in the comparison of canard position horizontally (Cases A2, B2, and C2), the canard position closer to the main wing will result in greater interaction.
The formation of a rolled-up vortex from the further canard position to the main wing will be easily lifted up, so the interaction effect becomes less. While the roll-up vortex formation from the canard with a closer position will remain in a low position above the main wing, this is seen in the cases A0, B0, A2, and B2. In lower canard vortex formation, the main wing flow is more maintained in a streamlined form and thus better flow stability. Flow stability makes the vortex core more stable and more difficult to breakdown. In other words, the lower the vortex flow from the canard above the main wing will delay vortex breakdown in the main wing.

Changes in the canard position vertically also produce differences in the vortex trajectory of the canard (Cases A0, A1, A2, and A4; and in the Cases B0, B2, and B4). In general, the increase in canard position causes the trajectory of the canard's vortex to rise above the main wing, thereby reducing interaction. However, the increase in flow height in the case of A1 is not significant in reducing flow interactions because the canard position is still low. This condition is shown in cases A0 and A1 which have no differences in location of the interaction of the flow between the canard's vortex and the main wing. While at a higher position than A1 (A2 and so on) the merging of the flow between vortices is more backward due to the reduction in flow interaction.
The canard position slightly in front of and above the main wing (case B2) can maintain the stability of the vortex core until the angle of attack is high and the position of the back of the main wing.
The most optimal results in all AoA conditions are obtained in the canard position above and front (Case B2). While at the high AoA, canard configuration in front of the main wing (Case C0) also gives good results. In the canard position on the top and front of the main wing gives the best value for the shift in the maximum Cl value between 5-10 degrees which indicates stall delay.
A wind-tunnel study to find the lift and drag characteristics of a low-aspect-ratio wing/body configuration from an angle of attack (AOA) of -8 to 50 degrees was conducted. A further study to find the comparative lift enhancement using the same wing/body with a close-coupled canard for wing/body angles of attack of 10, 22, 34, 40, and 48 degrees and canard deflection angles from -25 to 25 degrees was carried out. It was found that a properly-located canard enhanced the lift at all tested angles of attack, compared to the baseline wing/body configuration results. The lift enhancement was maximized in the post-stall regimes, reaching values up to 34%. A small improvement in lift-to-drag ratio was noted at all tested angles above 10 degrees angle of attack.
- document in fact outright points to close-coupled canard as an alternative to thrust vectoring
Stoll and Koenig demonstrated that the maximum lift of a close-coupled canard model was 34 percent greater than a non canard version of the same model. Furthermore, the increase in lift could not be solely attributed to an increase in wing reference area. The wing reference area of the canard-wing model was only 15 percent greater than that of the wing-alone model.
Er-El and Seginer found that a close-coupled canard placed upstream and above a 60-degree swept wing delayed the onset of wing-leading-edge vortex breakdown for an angle-of-attack range from 14 to 24 degrees. But significantly, the use of a close-coupled canard/wing did not always result in improved aerodynamic characteristics. Improved lift was dependent upon proper longitudinal positioning of the canard. Er-El and Seginer did not rigorously establish what this longitudinal position should be, but that was not the objective of their study.
Calarese tested a model with the canard placed above the wing and coplanar to the wing. At all angles of attack, the canard mounted above the wing created a more favorable interaction between the leading-edge vortices than the coplanar canard. The use of a canard placed above the wing caused a noticeable improvement in the lift-to-drag ratio for the tested angles of attack of 10, 16, and 19 degrees. The increase in the lift-to-drag ratio was 12 percent greater than the lift-to-drag ratio for the coplanar model. It was surmised that the more favorable lift-to-drag ratio of the model with the canard positioned above the wing was due in part to the vortex and wakef low of the canard missing the wing and therefore causing less interference. A more likely explanation is that downwash suppressed the flow separation of the wing and thus improved lift.
O'Leary and Weir demonstrated that the maximum CLusing a close-coupled canard was 20 percent greater and at an angle of attack 5 degrees greater than for a non-canard model.
It was shown that, with the canard in a high position above the wing, the overall lift was actually less than the wing/body alone configuration for angles of attack below 18 degrees. The interference that took place between the flowfields of the canard and wing that caused this lift degradation was not very well understood. It was thought that destructive interference occurred when the wash of the canard impinged upon the wing in an upward direction, which then promoted flow separation on the wing and thereby caused a loss of lift. Beyond an 18 degree angle of attack, the wash of the canard impinged upon the wing in a downward direction, and thereby delayed the onset of flow separation on the wing and correspondingly increased the lift.
Figure 16 shows the variation of CL with canard deflection angle for a wing/body AOA of 22 degrees. The maximum CL was 1.422 at a canard angle of 7 degrees. There was little data scatter and the curve was fairly smooth for all canard deflection angles tested. The lift varied in a strong nonlinear fashion from a CL of 0.97 to 1.36. A typical stall behavior was indicated, the lift coefficient leveling off to 1.30-1.35 after stall. When compared to the baseline configuration, lift was greatly enhanced for a canard deflection angle between -15 and 25 degrees. Positioning the canard from -25 to about -15 degrees degraded the lift below the baseline value. As the canard angle was increased from -15 to 7 degrees, lift was enhanced significantly. Lift was maximized at a canard angle of 7 degrees, where the CL was 34% greater than the baseline value of 1.061. From 7 to 25 degrees the values of CL decreased with an increase in canard angle; but, the comparative lift enhancement was still significant. At a canard deflection angle of 25 degrees, CL was still 24.5% greater than the baseline value. It should be noted that this enhancement is taking place at the wing/body angle of attack where the first stall occurred. Evidently the canard/wing interaction is preventing the wing separation from taking place, the canard vortex providing the energizing mechanism.
Figure 24 shows the comparative lift of the wing/body and the canard/wing/body configuration. As predicted by Lacey, there was little lift enhancement using a close-coupled canard at wing/body angles of attack less than 18 degrees. The maximum CL at 10 degrees AOA was only 3.4% greater than the baseline value. At 22 degrees AOA, where the first stall occurred, the lift was greater than the baseline value by 34%. This dramatic increase in lift is thought to be due to the downwash of the close-coupled canard impinging upon the flowfield of the wing, thereby delaying the onset of flow separation. At 34 degrees AOA, the lift was 9.4% greater than the baseline value. At 40 degrees AOA, where the lift was previously maximized for the wing/body configuration, the lift was 7.2% greater than the baseline value. In general, the lift enhancement was not as great where major separation did not previously exist for angles of attack tested in the baseline configuration. At 48 degrees AOA, where the second stall occurred, the lift was greater than the baseline value by 18.3% This great increase in lift is thought to be due to the vortex of the close-coupled canard constructively interfering with the vortex of the wing, thus delaying the onset of flow separation.
Figure 26 compares the baseline drag polar for the wing/body configuration with the drag polar for the canard/wing/body configuration using a canard deflection that maximized the lift for each wing/body AOA. For all tested angles of attack except 10 degrees, the lift was greater for the canard/wing/body than for the wing/body configuration at the same drag coefficient.
Figure 27 compares the lift-to-drag ratio for the wing/body configuration with that for the canard/wing/body configuration. For the canard/wing/body, the CL/CD at each tested AOA was greater than the baseline value for all tested wing/body angles of attack except at 10 degrees. At an AOA of 10 degrees, the CL/CD ratio was 34.5% less than the baseline value. The CL/CD ratios were 7.4%, 8.9%, 11.4%, and 10.4% greater than the baseline values at angles of attack of 22, 34, 40, and 48 degrees. Essentially, using a properly located close-coupled canard exacted a penalty in CL/CD only at low angles of attack, below a lift coefficient of 0.35. At higher angles of attack, the increase in CL/CD over the baseline value was as great as 11.4%.
(1) With a canard properly located longitudinally and horizontally, lift was enhanced at all tested wing/body angles of attack when compared to the baseline configuration. (2) The comparative lift increase using a canard deflection angle that maximized lift was the most dramatic at or near the stall conditions for the wing/body alone case. At a wing/body AOA of 22 degrees, where the first stall occurred, the lift was increased 34% over the baseline value. At a wing/body AOA of 48 degrees, where the second stall occurred, the lift was increased 18.3% over the baseline value. These increases in the lift are thought to be due to the vortex of the canard constructively interfering with the main-wing vortex, thereby delaying the onset of flow separation. Note that these enhancements already take into account the lift due to increased reference area.
(6) Using a close-coupled canard improved the CL/CD ratio at all angles of attack except at 10 degrees. The canard did cause a significant penalty of 34.5% in the CL/CD ratio at an AOA of 10 degrees. It should be noted that at 68 this cruise flight condition, where the AOA of the wing is small, the AOA of the canard is required to be large. The drag penalty is due to the high induced drag of the canard. At these cruise conditions, a high-AOA lifting canard could not be trimmed, and use of the canard is a poor way to achieve an enhanced lift. At this high-speed condition, a more likely situation would be to set the canard at a neutral A0A and use only the main wing for lift. In this case, only the main wing would be used as the reference area, and a more reasonable lift coefficient could be achieved with little drag penalty. In other words, the canard is only used at high angles of attack, and the apparent penalty at cruise conditions is provided by an unrealistic situation.
But Rafale cannot achieve 70 degree AoA but F-22 has displayed it publicly. If TVC jets got T/W ratio >1 & good avionics then they can dance on their nozzles or remain almost still. But a canard jet has to struggle so much to score a kill with its pilot sweating & screaming for breath & body under pain by G-suit squeezing by trying to take tight turns. TVC gets rid of such repeated painful sweaty effort.
Actually, it can. Gripen has managed to achieve 70-80 degree AoA sustained and 100-110 degree AoA maximum during the testing. Normal FCS however limits AoA to 30 degrees or so.

And what the hell are you writing? Pilot isn't "sweating and screaming", these are grunts that help deal with g forces. TVC doesn't help get rid of that, the only thing it helps is with nose pointing or if you get into a stall - but entering the post-stall envelope is a death warrant in any kind of a realistic combat scenario. You will be out of energy, soon out of altitude, and if you had to do something like that then it means you are already out of ideas.

Stop making up stuff.

If F-22 being bigger & heavy loses energy then from beginning itself it had plans for a stronger engine obviously.
Rafale empty 9.9T+ full fuel 4.7T+6 AAMs 1.3T=15.9T=35,000lbs. M88-2 has 50KN dry & 75KN ABthrust. AB-T/W ratio = 0.96
With all missiles used & 50% fuel, 9.9T+2.3T=12.2T=26,840lbs. AB-T/W ratio=1.25
So obviously the ATF team pushed for strong engines. F-119-PW100 has 116KN dry thust, 156KN AB thrust/eng. Empty 19.7T+ full fuel 8.2T + 6 AAMs 1.3T=29.2T=64,240lbs. AB-T/W ratio = 1.1
With all missiles used & 50% fuel, 19.7+4.1=23.8T=52,360lbs. AB-T/W ratio=1.33
First, F-22 weight of 19,7 t is the original production variant weight. So if you are using 19 700 kg for F-22, you should also be using 9 550 kg weight for the original production model of Rafale C. Both fighters had gained weight since, but I do not know how much fatter the F-22 had become.

Second, weight and size alone are a disadvantage.

So both sides will score kills but at this time my take is still that Rafale will loose more than 50% gunfights against F-22.
Well, your take is wrong.

When we see Su-35 & Su-57 their videos show better performace than F-22. While Su-57 is the only tandem tri-plane with Levcons whichmakes it perhaps most dangerous gunfighter, Su-35 removed canards & still retained its agility. My take is that F-22 might win a BVR but will loose a gunfight against them more than 50% of times. Others may disagree.
What, on air shows?

All 6th gen have to be better otherwise it is wastage of tax payer's money. The makers still have time to think. When we are talking abt a gen leap then we hav to make a better jet, simple. 6th gen is expected to have DEW to eliminate gun-fight. When sufficient KW laser pods have been tested on AH-64 & perhaps legacy jets then there is no doubt that 6th gen can mount a flat laser turret like a DIRCM.
As I have said, being generation ahead does not guarantee superiority. Fact that they are aiming to make 6th generation fighters better doesn't mean they truly will be.
 

Bhartiya Sainik

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I meant the channel wall.
That's among the hottest parts of engine, need to be Ttanium usually to withstand heat & structural integrity.

Why would that be a problem?
Still u can't figure out why it is a problem after giving picture & diagrams which don't match? :frusty::clap2::hail::clap2: Best of luck on ur own homework. I don't wanna go in circles.

Problem with converging panels is not that panels themselves will heat up, but rather that plume is visible from increased range of angles.
Plume is a very long thing but nozzles are just 1-2 ft. Converging them or leaving gap doesn't affect plume. If u wanna explain further then please use a drawing.


Rafale was said to have RAM paint even back in 1995:
View attachment 151217
R.I.P. 5th & 6th gen design R&D & tax payer's money. The entire world should purchase Rafale.


You know, thinking about what is being written would not be amiss. You use smileys, yet while I have made mistakes, you have shown yourself to be incapable of understanding basic concepts time and again.
After giving so many pics & diagrams, me incapable of understanding basic concepts, says a person who mixed up nozzle, cooling channel & blade cooling, hence the smileys :facepalm::pound::hail:
Whichever field we talk about - engineering, banking, law, architecture, arts, etc, we need to use terms & standards of that professional domain. So tech domain measurments have SI & imperial units, but u wanna use ur own personal units & standards, that's good for ur personal understanding but confusing to others.
U can write whatever u want in ur personal blog. Even most defence journalists, youtube channel owners, etc are not even technically qualified & make content like they want. Back in my college days i also wanted to mke my own blog site.


Total values do not matter in what I had written because we are talking about comparative performances. Lighter fighter will have less thrust, but can easily have far better acceleration and cruise speed performance. Why? If it has higher thrust-to-drag ratio, it will accelerate more quickly; if it has higher thrust-to-weight ratio, it will have better vertical maneuverability; if it has higher lift-to-drag ratio, it will be able to retain energy better; if it has higher lift-to-weight ratio, it will turn more quickly.
Tomorrow FCAS, Tempest, Su-57 pilots will say they reach Mach-1 at 40%, 50%, 60% throttle, what will it mean without mentioning total values? Have u seen any technical paper or speaker in seminar mentioning only %? NO. Why not? Bcoz those values depend on altitude, airframe design & load also. There are so many engine makers with series of engine, is there any engine considered as benchmark? NO. Is Rafale or any other jet the benchmark? NO.
My post was only on "Indian" Rafales that too on its engine, nozzle but u pulled me into comparative performance. After that also i shared only theoretical diagrams & pics from conceptual PoV until now lately i had to give some specific pics & calculations.
All the ratios u mentioned can be for light, medium, heavy jets, depends on multiple factors. I showed u the calculation that a heavy jet like F-22 has higher T/W ratio bcoz making a strong engine was a priority. Tomorrow FCAS & Tempest will require even better engines than F-22/35.
Before Rafale they tested Mirage-4000 also but cancelled it. Rafale could have been bigger jet but perhaps they didn't have a bigger better engine then. There are many geopolitical, economic, strategic, business factors including export to customers otherwise a product can fail or come under heavy criticism like F-35. Most European countries are small & have NATO support which may not require a cross-country huge jet like Sukhoi with double internal fuel. Hence light to medium jets like Grippen, EF-2000, Rafale have worked well in 4th gen category.
But now it seems the era of light jet is over or only for poor countries bcoz technology has progressed, more sensors, equipment, cooling, internal fuel & weapons, etc needed means more space & weight. Our LCA is a classic example of massive delays & "can't spit, can't swallow" hence they are inflating the same airframe to MWF & calling it Tejas MK2. U can consider it as 1 engine Rafale. Then we will have TEDBF which is so identical to Rafale bcoz we don't have our own original R&D money being 2nd most populous country with high corruption & scandal rates.
In future we will still see 1 engine jets like F-35, Su-75 but they won't be lean & slim like F-16 for example bcoz new tech consume space & weight.


Precisely. Which is why F-22 has thrust vectoring instead.
Every product cannot have everything otherwise its cost will be unsustainable. So choices & priorities have to be made. if u prioritize stealth u hav to exclude canards & include TVC & vice-versa. I'm not USA fan but it is a rich country & their firms like Lockheed & Northrop are leading some R&D since 1940s with vast funding & test facilities. How many countries have an entire X-series, space shuttle & jets like SR-71, B-2, F-117, etc? So as per their tests, they had to choose if they wan't to take risk of getting shot in BVR, or prioritise stealth & include TVC. And the result is that F-22 is costliest jet but Europe had to dump 5th gen & directly move to 6th gen to close the gap. All they could do is improvise with 4++ gen with composite materials & avionics within their budget.

And again, outcome itself doesn't matter as much. What matters is performance shown by Rafale, which shows that it doesn't really need thrust vectoring, as it is able to fight and retain advantage in slow-speed regime where thrust vectoring shines.
He was not "screaming for breath"; these "screams" are actually grunts whose purpose is to help pilot cope with G-forces involved in hard maneuvers. F-22 pilot will have been screaming just as much.
"Release stick" and "recover" are warnings due to loss of airspeed due to hard maneuvers. Any aircraft will stall out if it loses lift - F-22 is not "stall free", what kind of fantasy were you reading? Do you even know what stall is? Post-stall maneuverability does not mean stall free.
And what the hell are you writing? Pilot isn't "sweating and screaming", these are grunts that help deal with g forces. TVC doesn't help get rid of that, the only thing it helps is with nose pointing or if you get into a stall - but entering the post-stall envelope is a death warrant in any kind of a realistic combat scenario. You will be out of energy, soon out of altitude, and if you had to do something like that then it means you are already out of ideas.
Stop making up stuff.
So i never negated Rafales performance which u think. I said that i witnessed impressive performance of Rafale & other jets F2F, i hope u hav that experience. It is much better than a video. I also said it will take care of Pak & Chinese jets, what more u want me to say?
Your country also purchase Rafale so u r blind supporter of it, i don't feel compelled like that bcoz i simply consider both +/- points of any product.
Outcome is either death or survival, a live pilot or his/her coffin, that's the final thing. But it won't be same everytime. In every excercise, local or international, repeated BVR & dogfights are done & results could vary each day. You are so fixed on Rafale's performance that u don't wanna acknowledge anything about any other jet just bcoz ur country purchased it while i still acknowledge other jets where they desrve & raise concerns like with J-10C, etc. I already said that we should be smart customer, not marketing preys.

I'm aware of the pilot training during high G maneuvers but watch the 2nd video which u only shared in ur blog how those ex-pilots are making fun of the Rafale pilot & french propagandists. The HUD video also showed G & AoA values which Rafale's FCS allows max to avoid stall. The pilot was taking a lot of Gs due to high inertia. Go comment & discuss on their YT videos & share the screenshots here of their responses. You can watch Russian cockpit videos of MiG-29 OVT, Su-35, Su-57 during TVC maneuvers, they don't scream or even have to gasp much bcoz speed is so low which doesn't create high intertia & G. Rather it is like a roller coaster ride. Individual pilot physical tolerances may also differ. During F-22 & Rafale mock dogfight it also appears that F-22 may not be using much TVC bcoz during exercises they may disable some features as protocols like our MKI didn't use their radar to full limit at Red-Flag. So such minute details are seldom told to public. But TVC jet pilots won't scream, grunt, gasp like others, that's the whole idea behind good TVC to reduce effort, pain, but still maintain orientation, focus & situational awareness.
There are engineers who don't wan't pilot to struggle with high G, they don't wan't the pilot to tightly turn the plane in dogfight but make the missiles make U-turn. That's how technology evolves with time. Who doesn't wan't their pilots & soldiers to win a battle with minimum effort?
So i'm not making up any stuff, i'm merely sharing what i can find. But u don't wanna acknowledge any technical advancement of other platforms just bcoz ur country purchased Rafale & feel oblidged.

Lock is usually maintained with radar, and hard maneuvers can cause radar to lose lock. Radar also needs several seconds to establish lock. Nothing surprising there.
A typical radar lock was characteristics till 4th gen. Since 5th gen it is sensor fused avionics which even Rafale has to considerable extent. The optical sensors can maintain lock with help of digital image processing, just like a phone or CCTV camera detects people, their faces or a Tesla car recognizes so many objects & takes decisions to stop, speed or maneuver the car.
Similarly sensor fused avionics can detect a target by both active RF & passive EO sensors. But it depends on programming efficiency of engineers to control the radar & sensors & integrate them together.
If a radar takes several seconds to establish lock then either the H/w or the programming is obsolete. You can check this with some IT engineer in your friend circle if any.


F-22 and Rafale both have 360 degree sensor coverage. F-22 has EO (specifically, UV) missile warning system, while Rafale has IR DDM-NG MAWS, which also has 360 degree coverage. So no difference there, except F-22s system might have longer range while Rafale's would be better at detecting coasting missiles. And yes, it would also be better at targeting aircraft, assuming it receives upgrades necessary for that.
F-22 has 6-axis AN/AAR-56 DAS, precursor to F-35's AN/AAQ-37 DAS. The 6 +ve & -ve axis positions give spherical coverage with no blindspots. And the RF antennas are there on spine, belly, rear, wing edges, rudder, again spherical coverage.
While Rafale's 2 DDM MAWS do give hemi-spherical coverage but the airframe acts as blindspot for lower sectors. The belly holds the weapons & fuel tanks hence no 4th gen can mount sensors there, except on chin.
The 3 jammers & 3 RWRs doesn't seem to give spherical coverage but only in horizontal plane. They jam & warn of RF radiation, don't lock a target. I'm not aware of additional antennas if any.
"Indian" Rafales got 3 more SPECTRA sensors "on demand"!!, not seen on oter Rafales. I'm not sure if vertical +/- axis are covered bcoz belly has loads & spine doesn't show add-ons.
So there is a diff. b/w "would be" & "it is" better. technically MLUs don't have limits but budget has.
In the mock digfight b/w the clouds the Rafale lost locks & took time to lock like u said but the F-22 was maintaing a sensor-fused spherical awareness actively or passively at all times & angles, that was the whole idea since beginning. Its HUD will always maintain a target pointer. In some 1990s documentaries it was shown, deleted on YT & elsewhere now.
France will develop FCAS to have all these things, close the gap & hopefully have DEW also.



Not all canards are equal. J-20 uses long coupled canards, which are merely a control surface - forward positioned tail, essentially. In aerodynamics terms, J-20 is quite conventional. J-20 itself is also very large and heavy aircraft, which is additional minus.

What Rafale has are close coupled canards, which have absolutely nothing to do with J-20's long arm canards. I had written on close-coupled canards before, and you have list of literature at the end of the post. Read it.

Or if you do not want to, I found a few documents. Excerpts are below, but long story short:
1) close coupled canard delays stall onset, thus allowing higher maximum lift and improved lift-to-drag ratio at high angles of attack
2) close coupled canard delays vortex bursting (leading to above) best when it is close in front and above the wing; coplanar canard is much less effective, as is canard positioned far in front of the wing
3) due to the above, close-coupled canard above the wing produces lift-to-drag ratio some 12% better than a coplanar canard
4) in general, close-coupled canard improves both maximum lift and lift-to-drag ratio compared to either wing-only, wing-tail or other types of wing-canard configurations (e.g. long moment arm, close-coupled coplanar etc.)

- document in fact outright points to close-coupled canard as an alternative to thrust vectoring
:facepalm: U r artist in side-tracking the focus somehow after telling u repeatedly abt my post's focus. From where my post began at aft end of the jet & where it has landed to front end? You could have made ur own independent post on Rafale's aerodynamics or usage of canards. It is common sense by natural observation & simple physics that compared to a traditional tandem bi-plane design or a regular delta, a canard addition will give additional lift, but i didn't ask u to give huge documentation for exact position of canards. I thought naturally 2 decades back in 1990s even without reading that co-planar canards will partially disrupt air flow for wing hence being at different level is better. Since 25 years i'm maintaining a folder of such docs but my profession is different & have to manage family hence very less time to read everything. Imagine the kind of documentation flood i can bring here but nobody will read. Hence i prefer labeled diagrams & pics to which the members can correlate easily.
I wonder what the EF-2000, Sukhoi, Chinese guys have to say, although EF-2000 has canards at higher level.
Su-57 makers might say levcons are best, not canards. Our Naval LCA test jet has levcons but TEDBF is identical to Rafale, what a split in thinking.
From diagram of long & close canards J-20 doesn't have long ones, it is also just ahead of wing. I already said J-20 didn't impress me but J-10C is a concern. And larger jet will require larger canards. U can imagine a bigger Rafale, then canards may have to be increased also. MKI's canards are bigger than Rafale's bcoz it depends on jet's size, design, weight, agility, etc.
YF-23's V-tails were almost big as F-16's wing & they rotated very quickly. Who would think to rotate an entire wing like a stabilizer, but it all depends on design requirement & maker's abilities. Now Su-75 is coming up with V-tail & no canards. FCAS has lowered V-tail but no canards, Tempest has delta wings but no canards. I wonder what the 6th gen guys are up to?

Actually, it can. Gripen has managed to achieve 70-80 degree AoA sustained and 100-110 degree AoA maximum during the testing. Normal FCS however limits AoA to 30 degrees or so.
And what is FCS limit of Rafale? How much it got to during mock dogfight? 31?
Max limit demo is useless if FCS has to be limited & can't be used in battle, period. Either u survive or u r dead, that's all matters in end. Hence F-22 or any TVC jet was specifically designed overall with TVC to increase FCS limits get rid of unrecoverable stalls & spins.

First, F-22 weight of 19,7 t is the original production variant weight. So if you are using 19 700 kg for F-22, you should also be using 9 550 kg weight for the original production model of Rafale C. Both fighters had gained weight since, but I do not know how much fatter the F-22 had become.
I used 9,900Kg. Did 350Kg difference create a huge difference in T/W ratio or in the mock battle? NO.
If u think both jets gained weight then pls mention the potential components also.
Which is more capable, smaller, cheaper & lighter - a late 1990s PC or today's cheap range smart phone? Electronic component are getting smaller, lighter, cheaper, more efficient, so how r the jets becoming heavier?
And i myself showed u the variants of improved M88 engine, same might have occured for F-22 also.
If Rafale has F4 variant currently the F-22 is also going under 11 billion USD MLU Advanced Raptor Enhancement and Sustainment (ARES). It has already undergone Raptor Enhanced Development & Integration II (REDI II, readiness and software updates), etc.


Second, weight and size alone are a disadvantage.
But as per ur logic U just praised a lighter 6.8T jet Grippen above for high AoA, so it is far better than Rafale in dogfight i guess. And FCAS will be bigger & heavier, so will other jets.


Well, your take is wrong.
Hmm, says a guy who mixed up parts & concepts of engine & admitted to fail to understand why some jets need to have more space & weight.
:hail::hail:
As as per ur logic all bigger & heavier jets are worse than Rafale & all lighter jets are better than Rafale:doh: :hail::scared2::frusty:
U feel oblidged as ur country purchased Rafale, i don't. I praised it a lot where it deserves, i criticized it where it is lags. There is no product which has everything or it will be unsustainable.
BTW, it is not my take but that of millions of people including ex-pilots. Go comment on their videos, ok? But it is natural to have people on both sides, so i don't hav any issues at all with other people's belief. However, the HUD video itself tells a lot.

What, on air shows?
Rafale doesn't go to airshows globally? 😂


As I have said, being generation ahead does not guarantee superiority. Fact that they are aiming to make 6th generation fighters better doesn't mean they truly will be.
Apply same logic to compare Rafale with 3++ gen jets:nono: :pound::rofl::clap2:😆🤣:facepalm:
 

Picard

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That's among the hottest parts of engine, need to be Ttanium usually to withstand heat & structural integrity.
Yet on M88-2, it is one of the coolest parts when seen from the outside (granted, I think this is M88-3, but still, same thing).
M88-4.jpg


Plume is a very long thing but nozzles are just 1-2 ft. Converging them or leaving gap doesn't affect plume. If u wanna explain further then please use a drawing.
Please, do find one place where I claimed that it masks entirety of the plume.

Plume is not the same temperature throughout. It cools down over distance:
Plume-temperature-distribution-for-various-nozzle-shapes - Copy.png

2022-04-18.png


And what matters are viewing angles. Now, I do not think this is technically accurate representation, but illustrates rather well what I'm talking about:
2560px-Dassault_Rafale.svg - Copy - Copy.png
2560px-Eurofighter_Typhoon_line_drawing.svg - Copy - Copy.png


Difference may not be that large, but as you can see, Rafale's nozzle hides the hottest part of the plume from view from more angles than your typical circular nozzle does. And just as importantly, outer nozzle hides the inner nozzle from view.

R.I.P. 5th & 6th gen design R&D & tax payer's money. The entire world should purchase Rafale.
US 6th generation fighter is basically Dassault Rafale in its basic concept:

I do not doubt there will be technical improvements, though.

Whichever field we talk about - engineering, banking, law, architecture, arts, etc, we need to use terms & standards of that professional domain. So tech domain measurments have SI & imperial units, but u wanna use ur own personal units & standards, that's good for ur personal understanding but confusing to others.
These are not my "personal standards". You are using "standards" as an excuse to completely ignore the context and the entire point.

Tomorrow FCAS, Tempest, Su-57 pilots will say they reach Mach-1 at 40%, 50%, 60% throttle, what will it mean without mentioning total values?
It will mean a lot, actually. As I have already explained:
Turn performance is not dependant on total lift, it is dependant on lift-to-weight ratio.
Acceleration is not dependant on total thrust, it is dependant on thrust-to-drag ratio.
Climb performance is dependant on both of these ratios.

Capisci?

According to you, best dogfighter in the world would be Boeing 777...

Before Rafale they tested Mirage-4000 also but cancelled it. Rafale could have been bigger jet but perhaps they didn't have a bigger better engine then.
They could have easily made a bigger engine. Rafale A (Rafale prototype) used F404 engine, which is larger than M88-2:


Had they wanted a bigger engine back then, all they had to do was make M88 (which was being designed) a bit larger. M88 was sized to fit Rafale, not the reverse.

Most European countries are small & have NATO support which may not require a cross-country huge jet like Sukhoi with double internal fuel. Hence light to medium jets like Grippen, EF-2000, Rafale have worked well in 4th gen category.
Most European jets are designed for self-defense, hence no need for large fighters... or all-aspect stealth of offensive designs such as F-22, F-35, T-50 etc.

Every product cannot have everything otherwise its cost will be unsustainable. So choices & priorities have to be made. if u prioritize stealth u hav to exclude canards & include TVC & vice-versa. I'm not USA fan but it is a rich country & their firms like Lockheed & Northrop are leading some R&D since 1940s with vast funding & test facilities. How many countries have an entire X-series, space shuttle & jets like SR-71, B-2, F-117, etc? So as per their tests, they had to choose if they wan't to take risk of getting shot in BVR, or prioritise stealth & include TVC. And the result is that F-22 is costliest jet but Europe had to dump 5th gen & directly move to 6th gen to close the gap. All they could do is improvise with 4++ gen with composite materials & avionics within their budget.
My point was, F-22 didn't use TVC because it is the "best thing ever", designers used TVC because they had to compromise to maintain F-22's stealth.

Your country also purchase Rafale so u r blind supporter of it, i don't feel compelled like that bcoz i simply consider both +/- points of any product.
Cut the crap.

I supported Rafale even back when the only options being considered for HRZ were F-16 and Gripen, and when I had thought Rafale was a no-go due to being too expensive. I actually didn't expect Rafale to be even considered, let alone chosen, for Croatia up until it actually happened. And I still do not think Rafale was a best choice for us - back then and even today, I considered Gripen to be the best choice for Croatia, and not only for Croatia either.

Outcome is either death or survival, a live pilot or his/her coffin, that's the final thing. But it won't be same everytime. In every excercise, local or international, repeated BVR & dogfights are done & results could vary each day. You are so fixed on Rafale's performance that u don't wanna acknowledge anything about any other jet just bcoz ur country purchased it while i still acknowledge other jets where they desrve & raise concerns like with J-10C, etc. I already said that we should be smart customer, not marketing preys.
No, you don't. I do acknowledge other aircraft where they are good, but you seem to be intent on knocking down Rafale in comparison to just about everything.

I'm aware of the pilot training during high G maneuvers but watch the 2nd video which u only shared in ur blog how those ex-pilots are making fun of the Rafale pilot & french propagandists. The HUD video also showed G & AoA values which Rafale's FCS allows max to avoid stall. The pilot was taking a lot of Gs due to high inertia. Go comment & discuss on their YT videos & share the screenshots here of their responses. You can watch Russian cockpit videos of MiG-29 OVT, Su-35, Su-57 during TVC maneuvers, they don't scream or even have to gasp much bcoz speed is so low which doesn't create high intertia & G. Rather it is like a roller coaster ride. Individual pilot physical tolerances may also differ. During F-22 & Rafale mock dogfight it also appears that F-22 may not be using much TVC bcoz during exercises they may disable some features as protocols like our MKI didn't use their radar to full limit at Red-Flag. So such minute details are seldom told to public. But TVC jet pilots won't scream, grunt, gasp like others, that's the whole idea behind good TVC to reduce effort, pain, but still maintain orientation, focus & situational awareness.
Yes, because speed is so low that they would be dead.

And why F-22 wouldn't be using TVC?

There are engineers who don't wan't pilot to struggle with high G, they don't wan't the pilot to tightly turn the plane in dogfight but make the missiles make U-turn. That's how technology evolves with time. Who doesn't wan't their pilots & soldiers to win a battle with minimum effort?
The hell are you talking about? You need G capability to get into favorable position and also to avoid enemy missiles and other types of attacks. Regardless of the missile, its chance of hitting the target increases if it is launched from a favorable position.

If a radar takes several seconds to establish lock then either the H/w or the programming is obsolete. You can check this with some IT engineer in your friend circle if any.
Nope. Radar always took a couple of seconds to establish a lock. Back in 1970s, it could be 15 - 30 seconds, or even more.

In the mock digfight b/w the clouds the Rafale lost locks & took time to lock like u said but the F-22 was maintaing a sensor-fused spherical awareness actively or passively at all times & angles, that was the whole idea since beginning. Its HUD will always maintain a target pointer. In some 1990s documentaries it was shown, deleted on YT & elsewhere now.
You are again confused here. F-22 and Rafale both have 360 degree sensors coverage, but both aircraft primarily rely on radar (and IRST for Rafale) to provide a firing solution.

Rafale's DDM has enough angular accuracy to provide firing solution for potential laser jamming of IR missiles, yet I'm not claiming Rafale was using it to track the F-22.

U r artist in side-tracking the focus somehow after telling u repeatedly abt my post's focus.
I am correcting inaccurate claims. You have only yourself to blame after writing this:
It is definitely natural for canards positioned at front to control the pointing of a jet very well, simple physics, but not suited to stealth jet. What Chinese did with J-20 got lot of criticisms & their performance videos were not very impressive on agility.
By that, you have proven that you have no understanding at all of Rafale's aerodynamic design and characteristics, and close-coupled canards in particular. Yet you are trying to lecture me about how F-22s thrust vectoring makes it a superior dogfighter:
Rafale will loose most gunfights against TVC jets like F-22, Su-35.
So, you do not know what close-coupled canards actually do, you do not know what thrust vectoring's advantages and disadvantages are; you just think that "thrust vectoring = I WIN!" button, or at least that is how what you have written comes off.

Of course I will respond to that. So again, you only have yourself to blame for the offroading here.

Su-57 makers might say levcons are best, not canards. Our Naval LCA test jet has levcons but TEDBF is identical to Rafale, what a split in thinking.
Su-57 chose levcons for stealth reasons, I believe. Naval LCA used levcons for the purpose of reducing takeoff and landing distances, for which they are quite good.

And what is FCS limit of Rafale? How much it got to during mock dogfight? 31?
29 degrees with centerline fuel tank, 32 degrees with no tank. I do not remember how much it achieved during the dogfight, but certainly no more than 32 degrees.

Max limit demo is useless if FCS has to be limited & can't be used in battle, period. Either u survive or u r dead, that's all matters in end. Hence F-22 or any TVC jet was specifically designed overall with TVC to increase FCS limits get rid of unrecoverable stalls & spins.
And why do you think F-22 would also not be AoA-limited? Rafale's (and Gripen's) AoA limits are not there to prevent departure (that is, "unrecoverable stalls and spins"). Close-coupled canard aircraft can recover from those just fine - stalls and spins both - so they do not need AoA limits for safety reasons. They do however need them for practicality reasons: in combat, if you engage in post-stall maneuvers, you are already dead.

This is what close-coupled canards offered Gripen; and Rafale is, if anything, even more aerodynamically refined design (though not by much):
The Viggen aircraft had gone through a program of spin testing in the late seventies, that verified the rather benign high AOA characteristics of the canard layout, a fact contrary to what was known on some contemporary aft-tailed foreign fighters. So this was also an argument favouring the Gripen canard layout. Early investigations in vertical spin tunnels and tests in different rotary rigs and subsequent simulations, also pointed to acceptable spin behaviour.

A very substantial flight test program that recently was concluded for both the single as well as the two seat Gripen versions has also fully verified the excellent recovery capability, both in manual test mode and in the normal automatic mode. There exists a requirement in the Gripen project specification for a spin recovery capability, and if this can not be shown, a spin prevention system must not allow a departure to happen. Flight testing has also verified that the EFCS matches this additional demand. Double insurance might be said to exist.

(...)

The flow phenomenon, commonly called “dynamic lift”, perhaps more aptly called aerodynamic hysteresis, has been the object of intense interest in some countries for decades, not the least has this been the case in Russia. Its best public known, practical application may well be the awesome aerobatic display performed by test pilot V.G. Pugachev and his “cobra” turn in a Sukhoi Su-27.

When these hysteresis effects manifested themselves during high AOA/spin tests in the specially modified second Gripen prototype, they came as no surprise. Years prior, low speed wind tunnel tests with pitching motion of the model had already demonstrated the presence of marked unsteady flow effects, hysteresis, in the post stall alpha regime. Normal force hysteresis was most evident, but all the other components, except side force, had their share.

In the high AOA and spin tests that has taken place since 1996 and recently concluded successfully, the normal tactic was to initiate the tests with a near vertical climb with speed dropping off to near zero and a rapid increase of AOA up to extreme angles, and the aircraft could then be “parked” at 70 to 80 degrees of alpha. When giving adverse aileron input there, a flat spin with up to a maximum of 90 degrees per second of yaw rotation started and could then be stopped by pro aileron input. Recovery followed, whenever commanded.

(...)

Delta canard’s inherent good aerodynamics are:

· Stable detached leading edge vortex flow, high maximum lift coefficient.
· Positive trim lift on all lifting surfaces.
· Floating canard offers stable aircraft if EFCS fails.
· Good field performance (take off and landing), enhanced by special aerodynamic breaking mode.

· Battle damage tolerance good, “overlapping” control surfaces.
· Potential for future adaptations, like steep approach, fuselage aiming.
· Low buffeting levels made even better with leading edge flaps.

Spin recovery known to be acceptable for close coupled delta canard (not necessarily so for a long coupled canard configuration):

· Proven spin recovery capability for complete cg and AOR range.
· Nor risk of being trapped in a superstall, control authority exists.
So what, exactly, would thrust vectoring offer that canards do not offer already? Beyond maybe further improving takeoff-landing distance and cruise fuel efficiency, as you could use TVC to further adjust trim while optimizing control surfaces for low drag.

I used 9,900Kg. Did 350Kg difference create a huge difference in T/W ratio or in the mock battle? NO.
If u think both jets gained weight then pls mention the potential components also.

Which is more capable, smaller, cheaper & lighter - a late 1990s PC or today's cheap range smart phone? Electronic component are getting smaller, lighter, cheaper, more efficient, so how r the jets becoming heavier?
Fighter jets always gain weight over time as they receive additional capabilities and upgrades.

F-16A Block 10 is 15,600 pounds empty weight. F-16A eventually grew to 16 300 pounds.
F-16C Block 30 is 18 900 pounds empty weight.
F-16C Block 50 is 19,200 pounds empty weight.
F-16C Block 70 is 20 300 pounds empty weight.
F-16E Block 60 is 22 000 pounds empty weight.

If you don't understand something this obvious, how can I expect you to understand anything else?

But as per ur logic U just praised a lighter 6.8T jet Grippen above for high AoA, so it is far better than Rafale in dogfight i guess. And FCAS will be bigger & heavier, so will other jets.
Gripen has an issue with lack of thrust, but yes, I do expect it would be better than Rafale in a dogfight. Not sure about "FAR" better - Rafale would be superior in the energy department - but it is smaller, lighter and has smaller wing span. All of this, when combined with its excellent aerodynamics, means that it should have advantage in agility. Definitely when it comes to transients, which are crucial in a dogfight.

As as per ur logic all bigger & heavier jets are worse than Rafale & all lighter jets are better than Rafale
You know, if you are going to try and argue with me, at the very least you could try to understand my arguments. Otherwise you will produce completely illogical non sequiturs like this very quote.

I could write you down a very long list of jets that are inferior to Rafale in dogfight, despite being smaller.

Apply same logic to compare Rafale with 3++ gen jets
And again, your lack of logic is stupefying. There are fourth generation jets that are inferior to third generation counterparts, but Rafale is not one of them.
 

Shekhar Singh

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That's among the hottest parts of engine, need to be Ttanium usually to withstand heat & structural integrity.


Still u can't figure out why it is a problem after giving picture & diagrams which don't match? :frusty::clap2::hail::clap2: Best of luck on ur own homework. I don't wanna go in circles.


Plume is a very long thing but nozzles are just 1-2 ft. Converging them or leaving gap doesn't affect plume. If u wanna explain further then please use a drawing.



R.I.P. 5th & 6th gen design R&D & tax payer's money. The entire world should purchase Rafale.



After giving so many pics & diagrams, me incapable of understanding basic concepts, says a person who mixed up nozzle, cooling channel & blade cooling, hence the smileys :facepalm::pound::hail:
Whichever field we talk about - engineering, banking, law, architecture, arts, etc, we need to use terms & standards of that professional domain. So tech domain measurments have SI & imperial units, but u wanna use ur own personal units & standards, that's good for ur personal understanding but confusing to others.
U can write whatever u want in ur personal blog. Even most defence journalists, youtube channel owners, etc are not even technically qualified & make content like they want. Back in my college days i also wanted to mke my own blog site.



Tomorrow FCAS, Tempest, Su-57 pilots will say they reach Mach-1 at 40%, 50%, 60% throttle, what will it mean without mentioning total values? Have u seen any technical paper or speaker in seminar mentioning only %? NO. Why not? Bcoz those values depend on altitude, airframe design & load also. There are so many engine makers with series of engine, is there any engine considered as benchmark? NO. Is Rafale or any other jet the benchmark? NO.
My post was only on "Indian" Rafales that too on its engine, nozzle but u pulled me into comparative performance. After that also i shared only theoretical diagrams & pics from conceptual PoV until now lately i had to give some specific pics & calculations.
All the ratios u mentioned can be for light, medium, heavy jets, depends on multiple factors. I showed u the calculation that a heavy jet like F-22 has higher T/W ratio bcoz making a strong engine was a priority. Tomorrow FCAS & Tempest will require even better engines than F-22/35.
Before Rafale they tested Mirage-4000 also but cancelled it. Rafale could have been bigger jet but perhaps they didn't have a bigger better engine then. There are many geopolitical, economic, strategic, business factors including export to customers otherwise a product can fail or come under heavy criticism like F-35. Most European countries are small & have NATO support which may not require a cross-country huge jet like Sukhoi with double internal fuel. Hence light to medium jets like Grippen, EF-2000, Rafale have worked well in 4th gen category.
But now it seems the era of light jet is over or only for poor countries bcoz technology has progressed, more sensors, equipment, cooling, internal fuel & weapons, etc needed means more space & weight. Our LCA is a classic example of massive delays & "can't spit, can't swallow" hence they are inflating the same airframe to MWF & calling it Tejas MK2. U can consider it as 1 engine Rafale. Then we will have TEDBF which is so identical to Rafale bcoz we don't have our own original R&D money being 2nd most populous country with high corruption & scandal rates.
In future we will still see 1 engine jets like F-35, Su-75 but they won't be lean & slim like F-16 for example bcoz new tech consume space & weight.



Every product cannot have everything otherwise its cost will be unsustainable. So choices & priorities have to be made. if u prioritize stealth u hav to exclude canards & include TVC & vice-versa. I'm not USA fan but it is a rich country & their firms like Lockheed & Northrop are leading some R&D since 1940s with vast funding & test facilities. How many countries have an entire X-series, space shuttle & jets like SR-71, B-2, F-117, etc? So as per their tests, they had to choose if they wan't to take risk of getting shot in BVR, or prioritise stealth & include TVC. And the result is that F-22 is costliest jet but Europe had to dump 5th gen & directly move to 6th gen to close the gap. All they could do is improvise with 4++ gen with composite materials & avionics within their budget.


So i never negated Rafales performance which u think. I said that i witnessed impressive performance of Rafale & other jets F2F, i hope u hav that experience. It is much better than a video. I also said it will take care of Pak & Chinese jets, what more u want me to say?
Your country also purchase Rafale so u r blind supporter of it, i don't feel compelled like that bcoz i simply consider both +/- points of any product.
Outcome is either death or survival, a live pilot or his/her coffin, that's the final thing. But it won't be same everytime. In every excercise, local or international, repeated BVR & dogfights are done & results could vary each day. You are so fixed on Rafale's performance that u don't wanna acknowledge anything about any other jet just bcoz ur country purchased it while i still acknowledge other jets where they desrve & raise concerns like with J-10C, etc. I already said that we should be smart customer, not marketing preys.

I'm aware of the pilot training during high G maneuvers but watch the 2nd video which u only shared in ur blog how those ex-pilots are making fun of the Rafale pilot & french propagandists. The HUD video also showed G & AoA values which Rafale's FCS allows max to avoid stall. The pilot was taking a lot of Gs due to high inertia. Go comment & discuss on their YT videos & share the screenshots here of their responses. You can watch Russian cockpit videos of MiG-29 OVT, Su-35, Su-57 during TVC maneuvers, they don't scream or even have to gasp much bcoz speed is so low which doesn't create high intertia & G. Rather it is like a roller coaster ride. Individual pilot physical tolerances may also differ. During F-22 & Rafale mock dogfight it also appears that F-22 may not be using much TVC bcoz during exercises they may disable some features as protocols like our MKI didn't use their radar to full limit at Red-Flag. So such minute details are seldom told to public. But TVC jet pilots won't scream, grunt, gasp like others, that's the whole idea behind good TVC to reduce effort, pain, but still maintain orientation, focus & situational awareness.
There are engineers who don't wan't pilot to struggle with high G, they don't wan't the pilot to tightly turn the plane in dogfight but make the missiles make U-turn. That's how technology evolves with time. Who doesn't wan't their pilots & soldiers to win a battle with minimum effort?
So i'm not making up any stuff, i'm merely sharing what i can find. But u don't wanna acknowledge any technical advancement of other platforms just bcoz ur country purchased Rafale & feel oblidged.


A typical radar lock was characteristics till 4th gen. Since 5th gen it is sensor fused avionics which even Rafale has to considerable extent. The optical sensors can maintain lock with help of digital image processing, just like a phone or CCTV camera detects people, their faces or a Tesla car recognizes so many objects & takes decisions to stop, speed or maneuver the car.
Similarly sensor fused avionics can detect a target by both active RF & passive EO sensors. But it depends on programming efficiency of engineers to control the radar & sensors & integrate them together.
If a radar takes several seconds to establish lock then either the H/w or the programming is obsolete. You can check this with some IT engineer in your friend circle if any.



F-22 has 6-axis AN/AAR-56 DAS, precursor to F-35's AN/AAQ-37 DAS. The 6 +ve & -ve axis positions give spherical coverage with no blindspots. And the RF antennas are there on spine, belly, rear, wing edges, rudder, again spherical coverage.
While Rafale's 2 DDM MAWS do give hemi-spherical coverage but the airframe acts as blindspot for lower sectors. The belly holds the weapons & fuel tanks hence no 4th gen can mount sensors there, except on chin.
The 3 jammers & 3 RWRs doesn't seem to give spherical coverage but only in horizontal plane. They jam & warn of RF radiation, don't lock a target. I'm not aware of additional antennas if any.
"Indian" Rafales got 3 more SPECTRA sensors "on demand"!!, not seen on oter Rafales. I'm not sure if vertical +/- axis are covered bcoz belly has loads & spine doesn't show add-ons.
So there is a diff. b/w "would be" & "it is" better. technically MLUs don't have limits but budget has.
In the mock digfight b/w the clouds the Rafale lost locks & took time to lock like u said but the F-22 was maintaing a sensor-fused spherical awareness actively or passively at all times & angles, that was the whole idea since beginning. Its HUD will always maintain a target pointer. In some 1990s documentaries it was shown, deleted on YT & elsewhere now.
France will develop FCAS to have all these things, close the gap & hopefully have DEW also.




:facepalm: U r artist in side-tracking the focus somehow after telling u repeatedly abt my post's focus. From where my post began at aft end of the jet & where it has landed to front end? You could have made ur own independent post on Rafale's aerodynamics or usage of canards. It is common sense by natural observation & simple physics that compared to a traditional tandem bi-plane design or a regular delta, a canard addition will give additional lift, but i didn't ask u to give huge documentation for exact position of canards. I thought naturally 2 decades back in 1990s even without reading that co-planar canards will partially disrupt air flow for wing hence being at different level is better. Since 25 years i'm maintaining a folder of such docs but my profession is different & have to manage family hence very less time to read everything. Imagine the kind of documentation flood i can bring here but nobody will read. Hence i prefer labeled diagrams & pics to which the members can correlate easily.
I wonder what the EF-2000, Sukhoi, Chinese guys have to say, although EF-2000 has canards at higher level.
Su-57 makers might say levcons are best, not canards. Our Naval LCA test jet has levcons but TEDBF is identical to Rafale, what a split in thinking.
From diagram of long & close canards J-20 doesn't have long ones, it is also just ahead of wing. I already said J-20 didn't impress me but J-10C is a concern. And larger jet will require larger canards. U can imagine a bigger Rafale, then canards may have to be increased also. MKI's canards are bigger than Rafale's bcoz it depends on jet's size, design, weight, agility, etc.
YF-23's V-tails were almost big as F-16's wing & they rotated very quickly. Who would think to rotate an entire wing like a stabilizer, but it all depends on design requirement & maker's abilities. Now Su-75 is coming up with V-tail & no canards. FCAS has lowered V-tail but no canards, Tempest has delta wings but no canards. I wonder what the 6th gen guys are up to?


And what is FCS limit of Rafale? How much it got to during mock dogfight? 31?
Max limit demo is useless if FCS has to be limited & can't be used in battle, period. Either u survive or u r dead, that's all matters in end. Hence F-22 or any TVC jet was specifically designed overall with TVC to increase FCS limits get rid of unrecoverable stalls & spins.


I used 9,900Kg. Did 350Kg difference create a huge difference in T/W ratio or in the mock battle? NO.
If u think both jets gained weight then pls mention the potential components also.
Which is more capable, smaller, cheaper & lighter - a late 1990s PC or today's cheap range smart phone? Electronic component are getting smaller, lighter, cheaper, more efficient, so how r the jets becoming heavier?
And i myself showed u the variants of improved M88 engine, same might have occured for F-22 also.
If Rafale has F4 variant currently the F-22 is also going under 11 billion USD MLU Advanced Raptor Enhancement and Sustainment (ARES). It has already undergone Raptor Enhanced Development & Integration II (REDI II, readiness and software updates), etc.



But as per ur logic U just praised a lighter 6.8T jet Grippen above for high AoA, so it is far better than Rafale in dogfight i guess. And FCAS will be bigger & heavier, so will other jets.



Hmm, says a guy who mixed up parts & concepts of engine & admitted to fail to understand why some jets need to have more space & weight.
:hail::hail:
As as per ur logic all bigger & heavier jets are worse than Rafale & all lighter jets are better than Rafale:doh: :hail::scared2::frusty:
U feel oblidged as ur country purchased Rafale, i don't. I praised it a lot where it deserves, i criticized it where it is lags. There is no product which has everything or it will be unsustainable.
BTW, it is not my take but that of millions of people including ex-pilots. Go comment on their videos, ok? But it is natural to have people on both sides, so i don't hav any issues at all with other people's belief. However, the HUD video itself tells a lot.


Rafale doesn't go to airshows globally? 😂



Apply same logic to compare Rafale with 3++ gen jets:nono: :pound::rofl::clap2:😆🤣:facepalm:
I am not an expert nor have any knowledge about technical things you have written. Few months earlier I have asked a very senior officer of Airforce about use of TVC in real fight scenario. He said" Not much, it's good for air shows but in real dog fight aircraft looses energy and altitude and becomes sitting duck". Being incapable to understand these things I didn't ask anything further.
What's your take on this?
 

Bhartiya Sainik

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I am not an expert nor have any knowledge about technical things you have written. Few months earlier I have asked a very senior officer of Airforce about use of TVC in real fight scenario. He said" Not much, it's good for air shows but in real dog fight aircraft looses energy and altitude and becomes sitting duck". Being incapable to understand these things I didn't ask anything further.
What's your take on this?
The Su-30MKI guys, the pilots & the people who decided to have the TVC nozzle will be so delighted to meet this senior officer. 😂🤣
The MKI's AL-31 engine is not enough, it should have minimum AL-41 type or F119-PW100 type ideally so that T/W ratio is always >1 with A-A load also, at least 8 AAMs.
TVC can help get behind a non-TVC jet.
The kinematics of TVC can help escape BVR missiles also, it has to be done at precise time window.
It is natural evolution of technology.
So it is like 1st a person learns basic self-defence then advance martial arts.
But just like in a class every student is not a high ranker, similary later in every professional domain every person in any rank is also not having same capabilities.
And we have so many defence organizations since decades but it is only now we have started gaining good experience & making our own stuff. AMCA will also have TVC i think, in MK2 if not in MK1.
 

Shekhar Singh

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The Su-30MKI guys, the pilots & the people who decided to have the TVC nozzle will be so delighted to meet this senior officer. 😂🤣
The MKI's AL-31 engine is not enough, it should have minimum AL-41 type or F119-PW100 type ideally so that T/W ratio is always >1 with A-A load also, at least 8 AAMs.
TVC can help get behind a non-TVC jet.
The kinematics of TVC can help escape BVR missiles also, it has to be done at precise time window.
It is natural evolution of technology.
So it is like 1st a person learns basic self-defence then advance martial arts.
But just like in a class every student is not a high ranker, similary later in every professional domain every person in any rank is also not having same capabilities.
And we have so many defence organizations since decades but it is only now we have started gaining good experience & making our own stuff. AMCA will also have TVC i think, in MK2 if not in MK1.
Don't you think it's better to have tvc missiles instead of compromising the aircraft energy and altitude in dog fights by using TVC engine? F35 and all other new upcoming fighters like SCAF, Tempest or NGAD are mentioning adaptive cycle engine as it's feature but not TVC. I am not very sure whether they will use TVC engine or not but they are not mentioning it. May be I couldn't have seen yet.
 

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