Sukhoi PAK FA

Vijyes

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We don't have an engine.

The 125 kN engine is a myth.

It will take 20 years before GTRE can even get out a prototype.

We should stick to the I-30 engine that Russia has planned.

Otherwise IAF will be fighter-less in the coming 10 years.
125kN engine is a myth but 100kN ones are not myths. That is why I asked. 100kN engine F414 or EJ2000 are 1990 technology and can be replicated soon. 90kN ones are progressing well as of now.

IAF can use 90kN or 100kN engines based Tejas or AMCA instead of heavier FGFA. Supercruise is actually rarely used as 1 Mach speed consumes fuel at 2 times more than 0.8 Mach speed while offering only 25% better speed (I am speaking without after burners usage). The drag from air increases drastically after 0.9 Mach. The 0.3 Mach difference is not a deal breaker. Sonic boom also causes problems in visibility and poor stealth. F35 doesn't have supercruise as they did not deem it necessary.
 

TPFscopes

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125kN engine is a myth but 100kN ones are not myths. That is why I asked. 100kN engine F414 or EJ2000 are 1990 technology and can be replicated soon. 90kN ones are progressing well as of now.

IAF can use 90kN or 100kN engines based Tejas or AMCA instead of heavier FGFA. Supercruise is actually rarely used as 1 Mach speed consumes fuel at 2 times more than 0.8 Mach speed while offering only 25% better speed (I am speaking without after burners usage). The drag from air increases drastically after 0.9 Mach. The 0.3 Mach difference is not a deal breaker. Sonic boom also causes problems in visibility and poor stealth. F35 doesn't have supercruise as they did not deem it necessary.
1st Kaveri GTX-35VS is not capped for 90kn thurst , fire present specification there is 95+KN required thurst.
2nd for getting supersonic , supercruise provide the ability to get supersonic without putting ON fuel guzzler afterburners.

For difference between supersonic and supercruise
Supersonic is traveling in dry air of a temperature of 20 °C (68 °F) at sea level, this speed is approximately 343 m/s, 1,125 ft/s, 768 mph, 667 knots, or 1,235 km/h .
Most of the jets should turn on their afterburners to cross this limit , than it is known as supersonic.
But one who attain supersonic without using reheat/afterburner than it is said to be supercruise.
Cruising speed is a speed for a particular vehicle, ship, or aircraft, usually somewhat below maximum, that is comfortable and economical.

Cruising speed at supersonic = supercruise

Its dry thurst with supersonic speed = supercruise (in simple terms)
Supercruise basically depends on the aerodynamics. More aerodynamic jet need less thurst to attain supersonic and vice versa.
Kaveri GTX also possess quite similar figures of 52/95+KN.
http://defenceforumindia.com/forum/threads/amca-advanced-medium-combat-aircraft-hal.36/page-137

Stop the blabbering till the deal is signed. Either we make it or not. Quantity has a quality of its own. It is better to not have FGFA if the ToT is not as desired to eventually make it fully indigenous by 2030 including engine or if Russia offers something else in return.

We might as well start importing soldiers too otherwise
For FGFA based ToT which yet to come under JV development, all have to wait until the contract get signed. And good thing is that deal will getting signed soon.
You will see a flying FGFA by 2020. You may mark it as well.
 

Kchontha

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If FGFA arrives in the near future India will be having two fighter aircrafts (along with Rafale) which can supercruise. These two combination will be lethal. Along with super SU30MKI and AMCA India will be one of the best equip airforce in the world. For that to happen ADA has to speed up amca development.
 

Vijyes

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1st Kaveri GTX-35VS is not capped for 90kn thurst , fire present specification there is 95+KN required thurst.
2nd for getting supersonic , supercruise provide the ability to get supersonic without putting ON fuel guzzler afterburners.

For difference between supersonic and supercruise

http://defenceforumindia.com/forum/threads/amca-advanced-medium-combat-aircraft-hal.36/page-137


For FGFA based ToT which yet to come under JV development, all have to wait until the contract get signed. And good thing is that deal will getting signed soon.
You will see a flying FGFA by 2020. You may mark it as well.

Supersonic cruise is supercruise. I know that. That is why I wrote that no afterburners to be used. Even without afterburners, the airdrag itself will double at supersonic speed. As a result, the normal fuel requirement to combat air drag and maintain the 1+ Mach speed will also double. Air drag is dependent on velocity (not linearly). As the velocity crosses the speed of sound, sir drag suddenly rises sharply.

Supercruise is not recommended for that reason - air drag will burn down fuel, not afterburners. I have written this several times before but you seem to not even read before replying. Do you have some problems?
 

gadeshi

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Supersonic cruise is supercruise. I know that. That is why I wrote that no afterburners to be used. Even without afterburners, the airdrag itself will double at supersonic speed. As a result, the normal fuel requirement to combat air drag and maintain the 1+ Mach speed will also double. Air drag is dependent on velocity (not linearly). As the velocity crosses the speed of sound, sir drag suddenly rises sharply.

Supercruise is not recommended for that reason - air drag will burn down fuel, not afterburners. I have written this several times before but you seem to not even read before replying. Do you have some problems?
Wrong.
Drag doubles on transsonic (0.9 to 1.2) speeds, not after the Mach barrier (like 1.5M+).
Also your aircraft should be supersonic optimized to be effective and maneuverable at that speeds.

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gadeshi

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You will be able to see a FGFA in India by 2020.
Modifications will not take time because 41 our of 42 do not require structural changes. The remaining one is twin seat customisation which will be carried out by Russian side and for your kind information, its under development.

@gadeshi
Hope you will be able to address his concern.
Engine stealth is provided by several technical solutions as in engine itself (composite RAM-embedded compressor blades and ducts, radar blockers inside nozzles), as in airframe elements either (curved composite RAM-embedded air ducts, duct variable cross-section that curves the duct essentially when needed and cold plasma emitters to cover whole engine nozzle zones from behind).
I have posted rear cold plasma emitters photos earlier here as well as ducts variable curvature schemes either.

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TPFscopes

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If FGFA arrives in the near future India will be having two fighter aircrafts (along with Rafale) which can supercruise. These two combination wighal. Along with super SU30MKI and AMCA India will be one of the best equip airforce in the world. For that to happen ADA has to speed up amca development.
Supercruise didn't have any lethality features but it can only provide a longer range for strike Operations.

Fir AMCA , You might be able to see a flying Prototype by 2025.
As soon as we get the Airframe , than it will take very less time to fly first AMCA.
 

TPFscopes

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Supersonic cruise is supercruise. I know that. That is why I wrote that no afterburners to be used. Even without afterburners, the airdrag itself will double at supersonic speed. As a result, the normal fuel requirement to combat air drag and maintain the 1+ Mach speed will also double. Air drag is dependent on velocity (not linearly). As the velocity crosses the speed of sound, sir drag suddenly rises sharply.

Supercruise is not recommended for that reason - air drag will burn down fuel, not afterburners. I have written this several times before but you seem to not even read before replying. Do you have some problems?
You know everything but you still unable to understand what it is.
When we design any Airframe, we always kept all available resistance in mind. Air drag is an issue but we can reduce it via aerodynamic structure.
High pressure wind tunnel test provides all that data during its basic phases miaturised model, which is already cleared by AMCA.
Right now full scale of AMCA is under construction to study the stealth.
Than after we go for final production of Prototype and it will take maximum 2 years.
 

Vijyes

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You know everything but you still unable to understand what it is.
When we design any Airframe, we always kept all available resistance in mind. Air drag is an issue but we can reduce it via aerodynamic structure.
High pressure wind tunnel test provides all that data during its basic phases miaturised model, which is already cleared by AMCA.
Right now full scale of AMCA is under construction to study the stealth.
Than after we go for final production of Prototype and it will take maximum 2 years.
Air drag depends on drag coefficient. For the same structure/airframe, the drag increases as speed crosses the supersonic level. Unless you are saying that at supersonic speed the airframe changes into low drag one, the drag will increase drastically. Generally the supersonic cruise needs 1.5 - 1.7 times more fuel than subsonic cruise (NO AFTERBURNER in BOTH CASES) for same distance covered
 

TPFscopes

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Air drag depends on drag coefficient. For the same structure/airframe, the drag increases as speed crosses the supersonic level. Unless you are saying that at supersonic speed the airframe changes into low drag one, the drag will increase drastically. Generally the supersonic cruise needs 1.5 - 1.7 times more fuel than subsonic cruise (NO AFTERBURNER in BOTH CASES) for same distance covered
For your kind information, RAFALE & EFT can supercruise at 1.5 mach.
Do you understand the definition of efficient and economic?


Drag depends on the density of the air, the square of the velocity, the air's viscosity and compressibility, the size and shape of the body, and the body's inclination to the flow.
In general, the dependence on body shape, inclination, air viscosity, and compressibility is very complex.
 

Vijyes

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Wrong.
Drag doubles on transsonic (0.9 to 1.2) speeds, not after the Mach barrier (like 1.5M+).
Also your aircraft should be supersonic optimized to be effective and maneuverable at that speeds.

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Transonic speeds is from 0.9-1.4 Mach. At that point, the air drag rises exponentially - sometimes over 4 times. But even after 1.5Mach, the drag will be 30% higher than in 0.8Mach. The fuel consumption is always high in supersonic flights compared to subsonic ones (all other factors being constant like afterburner etc) by at least about 20-30% per unit distance.

I understand that maneuverability at supersonic speed needs supercruise. But the maneuverability at supersonic speeds is limited, even in supercruise. No dogfight takes place in supersonic speed. Even the ground attack is not done in supersonic speeds as reversing directions to return after attack will be difficult. Only advantage is that BVR missiles will have higher initial velocity. But that is about it.
 

Vijyes

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For your kind information, RAFALE & EFT can supercruise at 1.5 mach.
Do you understand the definition of efficient and economic?


Drag depends on the density of the air, the square of the velocity, the air's viscosity and compressibility, the size and shape of the body, and the body's inclination to the flow.
In general, the dependence on body shape, inclination, air viscosity, and compressibility is very complex.
That is what I said. You are also saying the same drag depends on velocity. But the drag coefficient itself is not constant and can change at different speeds (Cd in your equation). Cd increases severely as speed is in Transonic regions (0.9-1.4 Mach)
 

TPFscopes

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That is what I said. You are also saying the same drag depends on velocity. But the drag coefficient itself is not constant and can change at different speeds (Cd in your equation). Cd increases severely as speed is in Transonic regions (0.9-1.4 Mach)
You didn't read last sentence of my last post.
In general, the dependence on body shape, inclination, air viscosity, and compressibility is very complex.
It also clears that drag can be minimised by body shape , inclination etc.
 

gadeshi

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Supercruise didn't have any lethality features but it can only provide a longer range for strike Operations.

Fir AMCA , You might be able to see a flying Prototype by 2025.
As soon as we get the Airframe , than it will take very less time to fly first AMCA.
Wrong from beginning to the end.
Supercruise allows you to maintain medium to long range air-to-air combat by entering the most effective attack vectors to maximize your BVRAAMs launch vectors giving them maximum energy and the most optimal trajectory after launch and quickly change position after attack, maximizing missile avoid maneuver effectiveness.
And of course you can do enter-launch-exit-avoid-enter new attack in one continuous maneuver.

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TPFscopes

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Wrong from beginning to the end.
Supercruise allows you to maintain medium to long range air-to-air combat by entering the most effective attack vectors to maximize your BVRAAMs launch vectors giving them maximum energy and the most optimal trajectory after launch and quickly change position after attack, maximizing missile avoid maneuver effectiveness.
And of course you can do enter-launch-exit-avoid-enter new attack in one continuous maneuver.
you can also do the same with afterburners and jet like EFT and RAFALE too do the same with afterburners.

The basic use of Supercruise is to reducing the enemy repsonse time with greater range and more economically.
other jets ( without supercruise) can also do the same but they have to engage their afterburber which reduces their range. to enhance their range they should be equipped with Ext fuel tanks which reduces their weapon carrying capacity but also they are not economic.
 

Vijyes

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Sh-121 (N036 Belka radar, L-402 Gimalayi ESM/ECM and 101KS Atoll optical) avionics suit layout (without smart skin elements):
Can you explain what these different radars do? Or are these same radars but just placement differences?
 
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