Sukhoi PAK FA

MiG-29SMT

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Now as I mentioned earlier, for aircraft/wing, when you increase their AoA, their lift coefficient (CL) will increase until it reaches the stall point where there is airflow separation
The point just before the stall point where lift coefficient reached the highest value is called the CLmax.
The max instantaneous turn rate is often done at CLmax point, because that is the point where maximum amount of lift can be generated

Thrust vectoring technology has been successfully demonstrated on several previous programs to provide tactical maneuvering advantages in the very slow speed, very high angle-of-attack (AOA) flight regime.

The YF-22 used pitch-only thrust vectoring to provide enhanced pitch maneuvering authority at slow speeds.5
The F16 Multi-Axis Thrust Vectoring (MATV) program used production representative, axisymmetric thrust vectoring nozzle technology to further explore the tactical utility of thrust vectoring during one versus one and one versus two aircraft engagements against modern U. S. fighters at unlimited angles-of-attack.6 Both the production F-22 and the pre-production JSF (Joint Strike Fighter) aircraft will employ some form of thrust vectoring to enhance maneuverability. Almost all of the thrust vectoring utility explored to date has been concentrated in the low speed, high AOA flight regime. The overall goal of the F-15 Advanced Control Technology for Integrated Vehicles (ACTIVE) test program is to expand the flight envelope in which useful thrust vectoring is available to enhance aircraft performance, maneuverability, and controllability with production-representative nozzles (fig. 1).7

https://www.nasa.gov/centers/dryden/history/pastprojects/Active/pub_online/setp_d6.html
A number of close-in combat simulations were performed between X31 and F18 during the EFM program
, with the following results (Neutral start): 91% X31 wins, 3% F18 wins, 6% Neutral As a reference, similar simulations were performed, but this time the X31 was AoA-limited so that no Post-Stall was entered, the results were: 18% X31 wins, 46% F18 wins, 36% Neutral As a conclusion, the X31 is, in conventional flight, inferior to F18 from the close-in combat point of view, however the introduction of Post-Stall induces an advantage which not only compensates but also outweighs the baseline inferiority


Thrust Vectoring permits operation at much higher values of Angle of attack.

The use of the Nozzles as a complementary control surface allows the aircraft to better optimize its angle of attack (AoA) and minimize Flap Angle in stationary level flight for a given flight point
and load configuration, and by doing so to find the minimum drag condition, which in turn leads to strong benefits in SFC, and therefore range.

Once the Thrust Vectoring system has been sufficiently validated, it will be a primary control for the aircraft.
This means that it will allow a gradual reduction of existing conventional aerodynamic control surfaces such as horizontal and vertical stabilizers. This will have an impact, and there will be a reduction in: • Mass • Drag • Radar Cross Section (RCS)


Increased Sustained turn rate with TVNs

http://www.icas.org/ICAS_ARCHIVE/ICAS2000/PAPERS/RESERVED/ICA0534.PDF







ITP Aero has developed the only European thrust vector nozzle that allows the engine's exhaust air to be directed in several directions to substantially increase the aircraft's maneuverability.

https://www.itpaero.com/en/products-and-services/products/nozzles/








https://books.google.co.jp/books?id...F-22 f-16 thrust vectoring pitch rate&f=false
 
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StealthFlanker

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Thrust vectoring technology has been successfully demonstrated on several previous programs to provide tactical maneuvering advantages in the very slow speed, very high angle-of-attack (AOA) flight regime.

The YF-22 used pitch-only thrust vectoring to provide enhanced pitch maneuvering authority at slow speeds.5 The F16 Multi-Axis Thrust Vectoring (MATV) program used production representative, axisymmetric thrust vectoring nozzle technology to further explore the tactical utility of thrust vectoring during one versus one and one versus two aircraft engagements against modern U. S. fighters at unlimited angles-of-attack.6 Both the production F-22 and the pre-production JSF (Joint Strike Fighter) aircraft will employ some form of thrust vectoring to enhance maneuverability. Almost all of the thrust vectoring utility explored to date has been concentrated in the low speed, high AOA flight regime. The overall goal of the F-15 Advanced Control Technology for Integrated Vehicles (ACTIVE) test program is to expand the flight envelope in which useful thrust vectoring is available to enhance aircraft performance, maneuverability, and controllability with production-representative nozzles (fig. 1).7

https://www.nasa.gov/centers/dryden/history/pastprojects/Active/pub_online/setp_d6.html
Do you understand what is very high AoA, very slow speed regime? They essentially talking about post stall regime here, no words about STR whatsoever.



A number of close-in combat simulations were performed between X31 and F18 during the EFM program, with the following results (Neutral start): 91% X31 wins, 3% F18 wins, 6% Neutral As a reference, similar simulations were performed, but this time the X31 was AoA-limited so that no Post-Stall was entered, the results were: 18% X31 wins, 46% F18 wins, 36% Neutral As a conclusion, the X31 is, in conventional flight, inferior to F18 from the close-in combat point of view, however the introduction of Post-Stall induces an advantage which not only compensates but also outweighs the baseline inferiority
And they very conveniently forget what happen when X-31 went up against F-16 an F-15. The thing got massacred




Thrust Vectoring permits operation at much higher values of Angle of attack.

The use of the Nozzles as a complementary control surface allows the aircraft to better optimize its angle of attack (AoA) and minimize Flap Angle in stationary level flight for a given flight point
and load configuration, and by doing so to find the minimum drag condition, which in turn leads to strong benefits in SFC, and therefore range.

Once the Thrust Vectoring system has been sufficiently validated, it will be a primary control for the aircraft.
This means that it will allow a gradual reduction of existing conventional aerodynamic control surfaces such as horizontal and vertical stabilizers. This will have an impact, and there will be a reduction in: • Mass • Drag • Radar Cross Section (RCS)


Increased Sustained turn rate with TVNs

http://www.icas.org/ICAS_ARCHIVE/ICAS2000/PAPERS/RESERVED/ICA0534.PDF




When they said "TVC can help reduce RCS by becoming primary control for the aircraft that will allow a gradual reduction of existing conventional aerodynamic control surfaces such as horizontal and vertical stabilizers" what they really talking about is these tailless aircraft such as X-31, X-36. Because they actually eliminate the vertical tail, so that they can remove a corner reflector from the aircraft. They do not mean the RCS reduction come from lesser trim.
Also TVC will not increase sustain turn rate, whatever tiny amount of force you gain in the vertical direction from TVC, the same amount you will lose in horizontal. In other words, you gain "lift" but lost "thrust" to sustain the drag.










Pitch rate is not the same as turn rate.
Pitch rate is how fast you can turn your nose while your direction of travel remains the same. In other words, pitch rate is what you need in post stall regime
 
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MiG-29SMT

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Pitch rate is not the same as turn rate.
Pitch rate is how fast you can turn your nose while your direction of travel remains the same. In other words, pitch rate is what you need in post stall regime
you avoid the question that Sustained turn rates are increased and to achieve a a higher bank angle you need to increase the AoA tell me how do you obtain a higher AoA if you do not pitch the aircraft.


Therefore F-22 has much better STR and ITR than F-15 and F-16, of course you avoid reasoning what goes against your flawed logic because you can not accept that F-22 was able to keep with Rafale even without Helmet mounted sight which means it used regular agility, turn rates and roll rates, but of course you flawed logic just to win the argument and do not accept you are wrong makes you say F-22 is inferior in turn rates to F-16 something that is really really wrong and false


The quantity (T - D) is called the excess thrust and is related to the aircraft's ability to accelerate. Good fighter aircraft have high excess thrust. The ability to climb and maneuver involves the vertical net force as well as the excess thrust. Since the thrust force is already a large force for fighter aircraft, designers have sought ways to bring this force into the vertical equations of motion. With new mechanical systems it is possible to deflect the engine exhaust from the nozzle and cant the thrust vector at an angle. We will call this angle c. The resulting force equations are shown on the slide:

Vertical: L - W + T sin(c) = Fv

Horizontal: T cos(c) - D = Fh

where sin and cos are the trigonometric sine and cosine functions. The thrust now appears in the vertical force equation. This allows the aircraft to climb faster than an aircraft without thrust vectoring and to execute sharper turns than an un-vectored aircraft.
https://www.grc.nasa.gov/WWW/K-12/airplane/vecthrst.html

There are a host of potential benefits for incorporating thrust vectoring into the development of military aircrafts which include enhanced turn rate, improved maneuverability, vertical and short take-off and landing (V/STOL) capabilities, and elimination of control surfaces

http://www.rdi.rmutsb.ac.th/2011/di... on Vertical Take-off and Landing systems.pdf

 
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Lancer

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......................................
Great news, we need to eventually strike a deal for these (then work w/ a 3rd party to customize some aspects). It's the best way for us to get our hands on a stealth fighter, and will also help with the squadron shortfall.

Could end up teaching us some valuable lessons for AMCA development too.
 

StealthFlanker

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you avoid the question that Sustained turn rates are increased and to achieve a a higher bank angle you need to increase the AoA tell me how do you obtain a higher AoA if you do not pitch the aircraft.
Therefore F-22 has much better STR and ITR than F-15 and F-16, of course you avoid reasoning what goes against your flawed logic because you can not accept that F-22 was able to keep with Rafale even without Helmet mounted sight which means it used regular agility, turn rates and roll rates, but of course you flawed logic just to win the argument and do not accept you are wrong makes you say F-22 is inferior in turn rates to F-16 something that is really really wrong and false
The quantity (T - D) is called the excess thrust and is related to the aircraft's ability to accelerate. Good fighter aircraft have high excess thrust. The ability to climb and maneuver involves the vertical net force as well as the excess thrust. Since the thrust force is already a large force for fighter aircraft, designers have sought ways to bring this force into the vertical equations of motion. With new mechanical systems it is possible to deflect the engine exhaust from the nozzle and cant the thrust vector at an angle. We will call this angle c. The resulting force equations are shown on the slide:

Vertical: L - W + T sin(c) = Fv

Horizontal: T cos(c) - D = Fh

where sin and cos are the trigonometric sine and cosine functions. The thrust now appears in the vertical force equation. This allows the aircraft to climb faster than an aircraft without thrust vectoring and to execute sharper turns than an un-vectored aircraft.
https://www.grc.nasa.gov/WWW/K-12/airplane/vecthrst.html

There are a host of potential benefits for incorporating thrust vectoring into the development of military aircrafts which include enhanced turn rate, improved maneuverability, vertical and short take-off and landing (V/STOL) capabilities, and elimination of control surfaces

http://www.rdi.rmutsb.ac.th/2011/digipro/isft2015/fullpaper/ME24_A review on Thrust Vectoring and its effect on Vertical Take-off and Landing systems.pdf
Can you at least try to understand what you copy and paste instead of literally just repeating them like a parrot?
Firstly, yes, you need to pitch to get to higher AoA, but as I already explained earlier, when you increase AoA, the lift will increase, but so is the drag. In other words, while maximum instantaneous turn rate is done at CLmax, the maximum sustain turn rate is done at much lower AoA to minimize the drag. That reason while F-16 flight control law limit its AoA at 15 degrees at 9G even through CLmax is reached at 28 degrees AoA.
Pitch rate pretty much is irrelevant for STR because of 2 reasons: the first one is that AoA for STR is very small on order of 8-10 degrees AoA. The second reason is that you only pitch once then maintain that AoA to sustain your turn, unlike in post stall regime where you constantly pitching and yawing your nose around.


Second of all, max STR is done at the point where specific excess power is 0, in other words, the Ps =0 FPS line on EM diagram. If your specific excess power is already zero, which do you think will happen when you bend the TVC nozzle and effectively divide the horizontal thrust into vertical and horizontal???. The horizontal force will be lower and therefore, you lose that ability sustain whatever G value you were before.




Last but not least, a tight/sharp turn is often referred to minimum radius turn , it is absolutely not the same as sustained turn.
 

MiG-29SMT

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Can you at least try to understand what you copy and paste instead of literally just repeating them like a parrot?
Firstly, yes, you need to pitch to get to higher AoA, but as I already explained earlier, when you increase AoA, the lift will increase, but so is the drag. In other words, while maximum instantaneous turn rate is done at CLmax, the maximum sustain turn rate is done at much lower AoA to minimize the drag.



Last but not least, a tight/sharp turn is often referred to minimum radius turn , it is absolutely not the same as sustained turn.
all what you are saying is an excuse, real fact is sustained turn is increased with TVC nozzles you like it or not you admit it or not ITP is an jet engine manufacturer so all what you saying is cheap talk presented unrelated facts, basically what you are doing is trolling

There are several types of Thrust Vectoring Nozzles. For ... Eurofighter, in which the introduction of Thrust Vectoring ... Increased Sustained Turn Rate with T\/,s.
https://pdfs.semanticscholar.org/afc6/b4799245aa80d49ad5afb58293ad27a16ed6.pdf
 

panzerfeist1

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https://tass.ru/armiya-i-opk/7822257

“FEB 22, 23:03 Updated 23:10

“A small-sized inboard fuselage hypersonic missile was developed for the Russian fifth-generation fighter Su-57, a prototype of ammunition was created. This was reported on Sunday by TASS sources in the military-industrial complex.

"The enterprises of the Russian military-industrial complex have created a prototype of a small-sized air-to-surface hypersonic missile for intra-fuselable deployment on a Su-57 fighter," said one of the agency’s interlocutors.

Also my answer link on features that are believed to be present on the Su-57 https://qr.ae/p7EGFY
 

Lancer

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I really hope we get a few squadrons of these in the near future. Seems like an awesome plane.
 

Lancer

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It's a junk.........................
And yet it's the closest option India has to a stealth fighter any time soon. And please don't say AMCA either; it would be unbelievably shameless to claim India is anywhere close to building a high quality stealth fighter and fielding it in numbers while it hasn't even begun mass producing LCA MK1A's.
 

dude00720

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And yet it's the closest option India has to a stealth fighter any time soon. And please don't say AMCA either; it would be unbelievably shameless to claim India is anywhere close to building a high quality stealth fighter and fielding it in numbers while it hasn't even begun mass producing LCA MK1A's.
What is the story on it's RCS? Any official data or references?
 

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