This is a discussion on Thrust Vectoring for stealth fighters does it matter for China`s new J-20 and J-31? within the Air Force forums, part of the China Defense & Military category; The use of an independently controlled divergent section allows A9 to be optimised for any engine running condition at any ...
The use of an independently controlled divergent section
allows A9 to be optimised for any engine running condition
at any flight point, and has an improvement especially in
those conditions where one-parameter A9/A8 Ratio is not
For example, for a supersonic cruise case (Mach 1.2, altitude
36,000 ft, engine at Max Dry condition) of EJ200 engine on
Eurofighter, the use of independent A9 control could lead to
an improvement of up to 7% in installed net thrust relative to
the current performance. This is due to the combination of
two effects: increase of nozzle internal thrust; and reduction
of nozzle external drag.
In addition to thrust increase, independent A9 control also
permits reduction in SFC for certain flight pointshttp://ftp.rta.nato.int/public//PubF...051-PSF-11.pdf
Reduced take off & landing distance.
Increased thrust and reduced fuel consumption by means of afterbody drag reduction at supercruise conditions and nozzle exit area optimisation for the whole flight envelope
read the whole papers kyanges
however on the case of F-22 it does not increase thrust it reduces thrust; on the EJ-200`s case it does increase thrust because it is axisymmetric, but on F119`s case is non axisymmetric thus there is a change in exaust area and cross section from engine to nozzle
Last edited by MiG-29; 09-22-2012 at 10:41 AM.
there are somw fighter aircraft that does not need TVC,such as typhoon or F-16.
these aircraft are already highly manuever,adding TVC could do more harm to the pilot when attempting pull high G turn,creating a "black out".
problably why we do hear any news about TVC for J-10 .
Last edited by hardware; 09-22-2012 at 11:05 AM.
if you watch minute 7 of this video up to minute 9 you will see Mikhael Pogosyan saying lower IR signature for the flat nozzle 2D but this system reduces thrust, for such a reason Russian fighters use axisymmetric nozzles but they pay with higher IR signature than F-22`s
Thanks for the links. I'm working through them now.
all fighter jet engines can modify the radius of its nozzles.
F-15 ACTIVE on a test stand showing its 3D Pitch Yaw Balance Beam Nozzles (P/YBBN). These nozzles are mounted on the stock F100-299 engines and provide 20 degrees of thrust vectoring in any direction.
And thank you MiG-20 for the new thread
Thrust vectoring works by manipulating the direction of thrust, not the nozzle's exit area. Variable convergent-divergent nozzle works by changing the exit area, but not the direction of thrust. You can have both on an engine, but MiG-29 is being very disingenuous by misrepresenting a function of a variable convergent-divergent nozzle as that of TVN.
It seems PRC has been messing around with TVC nozzles at least since 1995. Some stuff I collected from the WWW :
Mid 90s 2D nozzles :
Early 2000s 3D nozzles :
2010+ 3D nozzles :