Originally Posted by
DOVES
Henra:
Esteemed sir
I must confess that even after almost fifty years of profession, my thirst for knowledge forces me to drink from any source in order to improve my knowledge.
However I have at least 70 textbooks in my library about aviation:
10 volumes from the basic course, and about 3 volumes per plane I've flown: MB 326, Viscount, DC8-62, DC8-43, Caravelle, DC-10, DC-9 30, MD-80, MD-83, MD, 11, B737-200, B737-230, B737-300, B737-400: 14 x 3 = 52 + 10 = 62.
Doves,
I do apologise if I stepped a bit harshly on your toes.
However, does any of those 70 Books (specifically those about conventional tail airliners) mention the behaviour you cited (violent pitch up upon stall)?
If so, could you maybe provide a Link ?
But why AF447 lost 38000 ft in 4 minutes?
Because trim + elevator kept it in the stall against all natural tendencies of a conventional tail. That was what I meant when writing 'simulate a deep stall' by applying copious amounts of trim + elevator.
It is pretty safe to assume that had elevator + trim been neutral the thing would have dropped the nose upon stall. More precisely without continued trim + up elevator it wouldn't have got there in the first place it would have lowered the nose prior to that. It was only elctronics that overruled the basic flight mechanics and changed the behaviour to some extent.