DU,
I'd agree with MFS & SP that a wing stall or spinning are not good examples of conservation or transfer of momentum. A better example would be roll coupling on the Starfighter.
MFS,
As an operational pilot, all our procedures permitted some ice/frost on lower surfaces but, of course none at all on the upper surfaces.
Now, since, on a conventional aircraft, the tailplane or horizontal stabilizer produces a downforce should not our procedures have permitted frost on top but required a clean surface underneath the tailplane?
BH!! just noticed I'm over 1k posts - sad old git!