TEDBF or ORCA Updates

scatterStorm

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gutenmorgen

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when you already have canards for maneuverability do you really need that additional complication? Weight-wise, TVC + engine > engine only. Besides close coupled canards also generate additional lift.
That is precisely why I am in favour of TVC. With TVC, you can lessen the use of canards, which is one most radar reflective part(when moving) on this aircraft. With tvc and semi recessed pylons, this will be as good as a proper 5th gen, with almost no compromises.
But the biggest advantage will be, shorter take offs. Actually on carriers that wont just be an advantage, it will be a necessity.
 

MonaLazy

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radar reflective part(when moving) on this aircraft. With tvc and semi recessed pylons, this will be as good as a proper 5th gen, with almost no compromises.
But the biggest advantage will be, shorter take offs. Actually on carriers that wont just be an advantage, it will be a necessity.
This is not the design brief of the TEDBF. It is NOT designed to be a stealthy fighter- Period! You can look up the TEDBF project director interviews posted in this thread from aero india- they want high pressure recovery on engine face so that it can take off from ACC deck with mouth watering payload- so no serpentine intake and any other compromise for stealth. We dont have small flat tops like Japan for thrust vectoring F-35Bs, IN has STOBARs which will depend on engine power and wings to generate lift in both the long and short runways of the ACC.

TVC may be helpful in STOVL or super maneuverability- but that is simple not the ask for TEDBF. When you have to lug gigantic anti ship missiles on external hard points then how to achieve stealth even if the airframe is stealthy? Isn't it better to have TEDBF fly autonomously few metres above the sea surface (must see Vishnu flying 100 feet above sea level if you haven't already) so you are harder to pick on radar? Logically this would be on the ASR for TEDBF:
  • fit in Vikrant and Vikramaditya lifts with folded wings
  • powerful engines- and do nothing stupid to reduce power available
  • huge payload capacity
  • huge range so max internal volume with a bulbous cross section
  • sea skimming flight on auto- also consumes lot more fuel but is important for the mission
  • ...others
Stealth is simply not the requirement. Also for canards just look up any good source of canard-wing interaction and see the benefits of close coupled canards. Here's a sample:

1616778261765.png


The use of a close-coupled canard on the SAAB Viggen also gave the aircraft much greater trim control compared to a tailless delta-winged aircraft such as the Mirage III. The lack of a horizontal tail on aircraft such as the Mirage III requires the use of elevons, which are deflected upward to create a down thrust to rotate the aircraft for landing and takeoff. The elevons have a much shorter moment arm than a horizontal tail, which in turn requires that the elevons be large to be effective. The elevons exact a weight penalty of as much as two tons, but more importantly decrease the effective lift of the aircraft, just the opposite of what is needed for enhanced takeoff and landing ability. The SAAB Viggen uses a large canard with trailing-edge flaps. During takeoffs and landings the Viggen has lift from the main wing, lift from the canard, plus lift from the downward-depressed main wing elevons. The result is that the Viggen has a much shorter takeoff and landing distance than the Mirage III.

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.

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.
 
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gutenmorgen

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This is not the design brief of the TEDBF. It is NOT designed to be a stealthy fighter- Period! You can look up the TEDBF project director interviews posted in this thread from aero india- they want high pressure recovery on engine face so that it can take off from ACC deck with mouth watering payload- so no serpentine intake and any other compromise for stealth. We dont have small flat tops like Japan for thrust vectoring F-35Bs, IN has STOBARs which will depend on engine power and wings to generate lift in both the long and short runways of the ACC.

TVC may be helpful in STOVL or super maneuverability- but that is simple not the ask for TEDBF. When you have to lug gigantic anti ship missiles on external hard points then how to achieve stealth even if the airframe is stealthy? Isn't it better to have TEDBF fly autonomously few metres above the sea surface (must see Vishnu flying 100 feet above sea level if you haven't already) so you are harder to pick on radar? Logically this would be on the ASR for TEDBF:
  • fit in Vikrant and Vikramaditya lifts with folded wings
  • powerful engines- and do nothing stupid to reduce power available
  • huge payload capacity
  • huge range so max internal volume with a bulbous cross section
  • sea skimming flight on auto- also consumes lot more fuel but is important for the mission
  • ...others
Stealth is simply not the requirement. Also for canards just look up any good source of canard-wing interaction and see the benefits of close coupled canards. Here's a sample:

View attachment 82956
With all due respect, I humbly disagree. I don't see the need for a stealthy nose cone (which does the opposite of decreasing drag) and conformal sensors if there was no need for stealth at all. No need for semi recessed pylons as well. From what I have read and seen (including that interview you are talking about. I have been a long time DDR follower), the need is for as much stealth as long as it doesn't compromise lift.
People on DFI have extremely radical views on TVC as seen on the AMCA thread and elsewhere. Some believe, its the end all be all of fighter aircrafts and it will kill anything in the sky. While others believe that its complete nonsense, because..USA. So I would really like to not get into that please. But TVC has its uses for short take-offs from stobars, especially if you want to carry more payload. I have posted the links for the research paper on this very thread before. The study was done by Mr. Vinayagam from ADA and Mr. Sinha from IIT Madras.


BTW, I am not saying that they should remove the canards. My hope is for the inclusion of TVC to have the best possible carrier aircraft and not against the inclusion of canards. Its just for the duration of the stealth mission when you have to stop the movement of canards. It will still generate additional lift while take-offs.
P.S. UK also uses F-35B's thrust vectoring on their carriers and they are stobar ones.
 

MonaLazy

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..which is perfectly fine as long as I am not paying you to agree with me.

I don't see the need for a stealthy nose cone (which does the opposite of decreasing drag) and conformal sensors if there was no need for stealth at all. No need for semi recessed pylons as well. From what I have read and seen (including that interview you are talking about. I have been a long time DDR follower), the need is for as much stealth as long as it doesn't compromise lift.
There is so much to learn here! I found this, didn't bother to read too much but just the intro says:

The chine generally results in stronger forebody vortices being shed compared to traditional fighters with smooth forebodies. For certain flight conditions these vortices interact with the wing leading edge vortices, and improve the maneuvering lift capabilities. However, for other flight conditions these vortex interactions are detrimental to the aerodynamic characteristics of the vehicle. This is especially true when the fighter experiences moderate to low angles of sideslip at angles of attack in excess of 25˚. Under these conditions abrupt asymmetric vortex breakdown leads to pronounced pitch-up and significant nonlinearities in lateral stability that could result in roll departure

Erickson and Brandon were amongst the first to investigate the nonlinear aerodynamic and stability characteristics of a chine-shaped forebody and delta wing configuration. They concluded that at high angles of attack the chine-wing vortex system was susceptible to severe asymmetries in the core breakdown positions in sideslip.
There are both + & - to chine. Since any design is all about balance and meeting the 90% use case- I'm sure ADA/IN chose well. The other problem is 30 years and we don't have a simple functioning engine- even if TVC is beneficial to TEDBF where is the compatible engine?

UK also uses F-35B's thrust vectoring on their carriers and they are stobar ones.
We need to ask what meaningful anti-ship payload the F-35B can carry in stealth mode.

Also can the F-35B carry an 1100 kg AGM-158C LRASM (Harpoon replacement) in its IWB? from wiki:

the F-35 has two internal weapons bays with four weapons stations. The two outboard weapon stations each can carry ordnance up to 680 kg for F-35B, while the two inboard stations carry air-to-air missiles
Final nail in the TVC coffin:

Similar in size to the A variant, the B sacrifices about a third of the A variant's fuel volume to accommodate the SDLF. This variant is limited to 7g.
also from the humble TEDBF wiki:

The TEDBF is expected to perform multiple roles like combat air patrol, air-to-air combat, anti-ship strike and buddy refueling
For the anti ship strike if even a F-35B with TVC has to carry the missile on external weapon stations then why over emphasize stealth or even TVC, forcing an overall compromise in range and payload?
 

gutenmorgen

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..which is perfectly fine as long as I am not paying you to agree with me.



There is so much to learn here! I found this, didn't bother to read too much but just the intro says:



There are both + & - to chine. Since any design is all about balance and meeting the 90% use case- I'm sure ADA/IN chose well. The other problem is 30 years and we don't have a simple functioning engine- even if TVC is beneficial to TEDBF where is the compatible engine?



We need to ask what meaningful anti-ship payload the F-35B can carry in stealth mode.

Also can the F-35B carry an 1100 kg AGM-158C LRASM (Harpoon replacement) in its IWB? from wiki:



Final nail in the TVC coffin:



also from the humble TEDBF wiki:



For the anti ship strike if even a F-35B with TVC has to carry the missile on external weapon stations then why over emphasize stealth or even TVC, forcing an overall compromise in range and payload?
That isn't the point. Whatever issues you have mentioned are the fault of F-35 design. Again, I am not against the TEDBF design in anyway. I am not saying we should remove canard or delta wing or make it like F-35 or to remove arresters and make vertical landings(the reason for high fuel consumption in F-35Bs). We don't need to have a much more complex tvc system like in F-35s because we don't need to land vertically. The main thing to focus here is the extra lift TVC provides to the F-35. The payload carry issues would have been much worse if they weren't using tvc. Because UK doesn't have catobar carriers, just like us, F-35s would have been unviable for them without tvc or without retrofitting their carriers with catobar. F-35B with a more complex tvc and less internal space would still carry more payload than F-35As if they were also flown from a stobar carrier. That is the only reason for them choosing F-35B.
Put TVC on a better airframe and you will see much better results. At least better results than what that same airframe would have had without TVC.
To put it simply, tvc will help the aircraft with additional payload carrying capacity for non stealth missions and with elimination of canard movement in stealth missions.

Also regarding chine, I haven't seen a definite positive conclusion(which isn't stealth related) from anybody, except in the case of SR-71 where the chine is really prominent. Without that, you can forget about any additional lift or stability(the main reason for their inclusion in SR-71). They need to be big/prominent enough to act as levcons. That isn't the case with TEDBF. And even then, that still doesn't give me the reason for conformal sensors and semi recessed weapon bays, but like I said stealth isn't the main advantage here. Its extra lift.

Regarding engines, unfortunately, you are right. We still don't have our own engines. But the nozzle(TVC) is something HAL/ADA can decide irrespective of the engine manufacturer. That design choice is with the aircraft designer and not the engine manufacturer.
 

MonaLazy

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Put TVC on a better airframe and you will see much better results. At least better results than what that same airframe would have had without TVC.
Can you point out any carrier based fighter in existence anywhere around the world that exploits TVC like you surmised? If there is none that could mean only one thing..

nozzle(TVC) is something HAL/ADA can decide irrespective of the engine manufacturer. That design choice is with the aircraft designer and not the engine manufacturer.
I'd be really surprised if that was true. Each and every component in a jet engine is custom built for that particular engine to work with each other- the air+fuel flow is so complex, different altitudes, different flight regimes, angles of attack among several other variables to consider. It is not uncommon to have different super specialists (and IP!) for different parts of the same engine. I dont think it is possible to simply slap on a nozzle to any engine and voila TVC!
 

gutenmorgen

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Can you point out any carrier based fighter in existence anywhere around the world that exploits TVC like you surmised? If there is none that could mean only one thing..
F-35Bs on Uk carriers are a prime example of this. Otherwise they would have gone for F-35As. Takeoff distance is closely coupled with how much payload you can carry. If you increase the payload, you increase the takeoff distance. Take Mig29s as a example. The airforce version has a 2 ton more MTOW than the navy version, which has the same engine. That is because Mig29K is limited by the carrier's short takeoff distance. Similarly F-35A carries more payload than B version not just because it has more internal space but also because it takes off from a longer runway on land.
F-35B utilises TVC for this purpose quite beautifully. There aren't that many examples because carriers are not exactly common. US and France have catobars so they don't need another complication. Everyone else is rather new to carriers but maybe we will see exactly that in the future, provided we don't get catobars. And if you have the time, please read the study that I linked earlier. It is on this very topic.



I'd be really surprised if that was true. Each and every component in a jet engine is custom built for that particular engine to work with each other- the air+fuel flow is so complex, different altitudes, different flight regimes, angles of attack among several other variables to consider. It is not uncommon to have different super specialists (and IP!) for different parts of the same engine. I dont think it is possible to simply slap on a nozzle to any engine and voila TVC!
It is true. While TVC is a more complex nozzle type and much more closely coupled with an engine than other nozzle types, It isn't a part of the engine. But they do need to be designed specifically around an engine. F-35 is an example here as well. The lift fan section is developed by RR and the engine by P&W.
Take J-20 as an example. They had serrated nozzles on their russian engines.
When you buy engines, they don't usually come with nozzles, unless its there in the contract. You need to fine tune the engines for your aircraft anyhow. With FADEC, these things have become much easier.
Finally, check out this interview by HVT from DDR. Start watching from 8:15 mark or watch the whole interview. Its very informative.

 

saketkr

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Women- can stick your kukuduku in her orifices when you feel horny
TEDBF- can do that ( CAUTION - not while the engine is on)

TEDBF - 10
Women - 0
Can we keep some decency in our chit-chat when posting on a public forum, unless we have assumed that we don't have any female members on the forum. I for once would like to disagree with the language used here, considering all of us on this forum are well-cultured. We are in this thread to discuss and learn about TEDBF not about human anatomy!
 

Lonewolf

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So after reading some article and all .

Amca engine is supposedly to be 110kn class , means 110kn+ class , so let's do some basic calculation

Engine. Dry thrust. Wet thrust
F119 116 kn. 156
F 135 -600 120. 180
M88. 50. 75
Ej 200. 60. 90


So one conclusion ,that can be draw. Reheat thrust is 3/2 *dry thrust , this is common among all , except f 119 , especially European design

So if dry thrust of amca engine us to be calculated like this for guess is about 75 kn.

Also rolls Royce said it will have a development potential of about 20-25 percent , that makes it 93 kn thrust dry at max .
For the first variant we develop , total thrust is 150 kn ,with high power generating for avionics , as it is newer generation it will have more power than f 35 , 160 kw , atleast .

Also RR is experienced with f 136 engine where inlet temperature was 2150+K ,which provides better fuel efficient engine .

So basically we will have a fighter with 150kn dry thrust at least , 230 kn about wet thrust , with specific capability to Operate in indian condition , enough power for avionics , as engine and ew suite will be GaN based , we will have power for some DEW in case we employ it .

Will give impressive twr .

Now consider the advanced variant with full utilization of design , ie about 93 kn dry thrust and 140 kn wet thrust each , that would provide a suitable powerplant for replacement for our flanker .

Not only we will be fielding a advanced jet but a most optimum jet , better availability (initial goal ) , less maintenance (primary goal ) , much efficient engine (mk 2 ) , large weapon carrying capacity (mk 2 with sidebays , bigger main bays ,maybe ) , kne of the best avionics , one of the refined design , and above all .

It is our f 35 , mk1 ,and f 22 mk 2 , tedbf would be our f a 18 but tons betrer than that , tejas mk 2 desi f 16 .

Orca if materialize with indigenous engine is f 15 category .
 

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