Aeronautical Engineering/Unusual aircraft upsets/problems
Hello, aerospace student first year here, working on a project about airplanes (aerodynamic) upsets, I would like some help if you know any, especially aerodynamic upsets like aileron snatch, rudder lock-in (reversal), tailstall, inertia coupling, dutch roll, aeroelastic flutter, divergence, control reversal, pilot induced oscillations or unusual failures/problems inflight during flight related to aerodynamic phenomenon or structural issues, stability. If you know any others phenomena of this kind, please help. Thanks!
Sorin - that is quite a list. I did a study of deep stall years ago (Soderman and Aiken: Full-Scale Tests Of A Small Unpowered Jet Aircraft With A T-Tail. NASA TN D-6573, Nov 1971) that found that a T-Tail aircraft can lock into stable stall. Basically, the wing wake washes out the tail. But we also found that if the aircraft did not reach deep stall, it would enter stall and roll one wing down. One wing would stall before the other. Both of those situations (deep stall, stall-induced roll) are aerodynamically bad and might be considered similar to your upsets.
Years ago our flight-test group had a film showing pilot-induced oscillation that was very scary, but I don't know if that film exists anymore.