Originally Posted by HN39
Machinbird,
I'd be interested in the definition of AoA at 0 airspeed and in the accuracy of the value you observed.
As you no doubt surmised, unless you are flying a thrust vectored overpowered aircraft such as an F-22, the transit of 0 airspeed is just that, transitory. You pull the nose up to vertical and let the speed bleed off until there isn't any. The indication generally stays close to 0 AOA unless you develop a pitch rate as you lose control authority. Then, as the aircraft backs down, the indicator flips to one of its limits and the aircraft then flips over briskly to point its nose down (with some oscillation) and the AOA stabilizes back at usable values. If you are wise, you will wait until you have some g available before attempting any control inputs.
None of this has any applicability to transport aircraft other than the deviation from correct AOA indications is brief and of no practical concern to the pilot. One would hope that a flight control system that experiences this type maneuver would also avoid making control inputs during the brief period that control authority is minimal. AOA at 0 airspeed is, of course, undefined.