PPRuNe Forums - View Single Post - Inverted, unloading and reducing angle of attack on Modern Jet Aircraft
Old 23rd May 2017, 15:01
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Originally Posted by bohpilot
We are having a real active discussion at work on upset recovery training on a jet and in particular High angle of attack when inverted. My understanding has always been that even when you are inverted with an high angle of attach on the wing you have to unload the wing by "pushing".

The argument comes back that if you "push" when you are inverted then you are going to make the situation worse.

Would welcome some advice.
As in any airplane in any attitude, if you want to unload the wing (and move away from a stall) you have to move the stick toward the middle, in order to reduce the AOA. If the stick is back and the AOA is high, that means moving it forward. In the high attitude inverted situation, this will allow the (presumably) low-speed critical airplane to pitch below the horizon (via the natural, longitudinal stability, or "lawn darting" if you will) with an AOA close to zero, and therefore a stall speed close to zero. Just the way you want it.

In any technical discussion by non-engineers, a lot of (even basic) detail can get lost in assumptions and mistellings. You didn't say what your friend says will be made worse, but I'll take a stab. He probably took "push" to mean more than moving the stick forward toward neutral, but rather past neutral and even more forward into negative AOA and therefore negative G. That could then prevent the nose from coming below the horizon, and force the speed to decay even more (not to mention what will happen inside a transport plane at negative G).
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