Forum: Air Power

There is increasing use of thrust-vectoring nozzles in aircraft such as the F-22, SU-35, and new variants of the MIG-29.

I'm interested to hear a discussion on how thrust vectoring can be applied in both offensive and defensive BFM.

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The current generation of TV jets use the nozzles to help the driver point the nose where he needs it to prosecute an attack and for precision handling in a low-speed, high-AOA regime. But back in the '82 Falklands War the Brits used a technique in their Harriers called VIFF-ing (Vectoring In Forward Flight). It doesn't do much for you in wings level flight but in a turn you can dramatically decrease your turn radius by vectoring the nozzles downward a bit (not full down) while pulling thru the turn. It can be used both defensively (to evade an air attacker or ground threat) and offensively (to quickly bring your nose to bear on an enemy jet or pull lead on it if needed).

Can't recall if they said it was effective or not but I heard one Brit driver say he was defensive against an Argentine jet and he VIFF-ed so quickly he practically vanished in front him. Laughing

The Harrier nozzle control is fully manual whereas the newer TV jets have electronically controlled nozzles. So any kinda Harrier-style VIFF-ing prolly won't happen in a Raptor or Sukoi, although I'm sure both have classified pitch rates that aren't being divulged or displayed at airshows. Whistle

For normal flight and fight, if you need your airframe to turn more sharply, then you can just increase the size of your airflow deflection panels.
You will pay aproximately 1/20th of overall cost+complexity compared to adding vectored thrust.
A lot of that cost will be in the flight control software that has an unusual dynamic to factor in.
Unless your airspeed drops very low, you just get so much more angular defection force from old school horizontal stabs that you need to start making up semi-fictional scenarios to keep investing in vectored thrust.

Thats why so few buyers have been willinng to pony up for it.
Oh I forgot, Airshows...that is where vectored thrust pays off the most methinks.
The F-22 may make use of vectored thrust to stay agile in the very high altitude flight profile???

Forum: Air Power

Thrust Vectoring in BFM