How does an airplane do a Kulbit manoeuvre?

Question

Some time ago, I came across a GIF of a Russian military airplane doing a Kulbit manoeuvre (Probably for showoff). How, in terms of control surface movement, does an airplane to the Kulbit?

^{Source: Reddit}

Answer 1

The Kulbit maneuver is a variation on the Cobra maneuver (Pugachev's Cobra) with a higher pitch rate and continuous positive pitch rate throughout the maneuver. It requires two things:

• A docile pitch behavior of the airframe over the full angle of attack range of 360°. Docile means that the pitch moments stay low and do not change abruptly with the angle of attack.
• Thrust vectoring nozzles to keep the pitch rate up.

An electronic flight system is helpful to make execution easier, but is not strictly required. Also helpful is an engine-intake-combination which does not stall the compressor if the outer flow is reversed briefly. As you can see, the control surfaces only play a minor role - they are only important initially to start the pitch-up motion. This is done by negative elevator and/or positive canard deflection.