Has anyone here actually experienced asymmetric flap deployment? I haven't seen it in 50 years of flying.
Well, sort of! The flap system had been disassembled, lubricated then reassembled. When the splined drive shaft was refitted, the guys managed to insert a shaft locking bolt through the 'female' socket without ensuring the 'male' shaft was fully inserted. All functional Passed. Coincidentally on the first trip afterwards we were flying a few simulated circuits at height. During one selection, the splined shaft fell out of the drive unit. Fortunately it was in a fairly advanced aircraft that sensed flap shaft rotation at both outboard flap screw jacks. When one stopped turning it froze the flap system before any significant assymetry occurred.
Oh, the maintenance instructions did include a warning to ensure the splined shafts were fully inserted prior to fitting the locating bolt!!!