Cannot achieve a safe cobra maneuver

[Nooch]

Hi!

 

Do you guys have any tips to perform the cobra properly? From my understanding we just have to disable the electronic flight assistance (S key), pull hard on the stick and then push it away to end the maneuver...

 

Problem is, whenever I do this, I get the first part right i.e the aircraft pitches up very quickly and stays vertical for a brief moment, but then I lose all my momentum and the aircraft stalls and is very hard to recover. Most of the time my aircraft spins around while stalling and the engines go off, making things totally uncontrollable.

 

Those who know how to do it right, please, I need your take on this! Thanks.

Edited November 13, 2014 by Nooch

[Thumper1606688436]

1) Speed approx. 550kph

2) Disengage flight assistance (S Key)

3) Pull hard until plane pointing vertical & center stick.

4) re-engage flight assistance (S Key)

5) The nose should naturally drop back down but you can give a little forward assistance.

[Joe Kurr]

Give full power (no AB) when you pull back on the stick so your engines have time to spool up during the manouver.

Remember to press S again after the aircraft pitches up or you will stay in direct control mode.

 

When the nose falls back down, pull the stick back a bit to ease the drop.

[159th_Viper]

Excerpt from first-hand account of a Marine Test Pilot's flight out of Ramenskoye airfield in a SU-27:

 

 

The Cobra

........

 

We discussed the Cobra in our flight brief. It went something like this:

 

Me: "I would like you to show me the Cobra maneuver."

Kvochur: "Yes, sure."

Me: "What entry airspeed and altitude should we use?"

Kvochur extended the fingers of both hands in a calming gesture and said: "I show you."

 

That was it. I looked toward our interpreter for a read on this physical punctuation, but she returned the internationally universal shoulder shrug. So I took his brevity as an admonition against prying too much into this top-secret aerobatic phenomenon and made a mental note to be prepared to absorb as much technical data as I could during his demo.

 

When I was ready for the demo, he had me turn off the angle of attack limiter and another fly-by-wire switch that was never explained completely to me. Then he said, "I do one. We do one. You do one." The setup was 350 kilometers per hour (approximately 190 knots) in straight and level flight. He pulled the stick all the way back, and the airplane pitched nose up past vertical. In a little more than one second, we were more than 90 degrees nose up after the stick pull. He recovered the plane back to straight and level, and the maneuver was complete. The speed was about 90 knots as the nose approached the horizon. During the "We do one," I was again surprised at the non-aggressive control inputs. He used large pedal displacements during the first half of the pitch-up then transitioned to differential throttle control to keep the roll and yaw minimized. For the nose-down recovery, the stick was moved well forward but not all the way. Differential throttle that gave way to rudder-pedal activity essentially kept us wings-level throughout. My turn: I replicated what I had just ridden through, and the results were the same. I didn’t get past 90 degrees nose up like Kvochur, but I was awed anyway. Despite the radical attitude change, the entire maneuver was completed under 3G. Throughout this seemingly suicidal contortion, the engines never complained, and there was no implication of an impending loss of control.

 

Fun complete, I switched the limiter and fly-by-wire switches back to their normal positions, and we headed back.

 

............

[Nooch]

Alright I understand why I was stalling every time: I was pushing back on the stick too hard to end the maneuver, resulting in the aircraft pitching down too fast and becoming uncontrollable.

But even after practicing a while I still can't get it clean: the cobra makes me climb ~350 meters (~1000 ft) which seems like way too much and I often roll on the sides a little bit...

[Lizzard]

for me it works better to first pull the Stick fully back (at ca 450 kmh) and then press s...if I am vertical I press s again and push the Stick forward..but I am still a bit away from a perfect cobra..my Plane tends to roll:joystick: