The steady-state aerodynamic stall, much beloved of textbooks, is always at the same angle of attack. No dispute about that. Except of-course, that in a real aeroplane, as opposed to a wind tunnel, there's rarely such as thing as a steady state.
The piloting stall also may not be a true aerodynamic stall. The stall, as seen by the pilot can involve elevator authority (and hence CG position, also power setting), wing drop (potentially a function of residual aileron deflection, differential amounts of dead flies on the wing, slight mis-setting in flaps), sideslip (rudder input, rudder trim setting), lateral CG (fuel imbalance).
If you've ever had an aeroplane "mush" on you for example, this is a pitch limitation, and really very little to do with the aerodynamic stall of the wing, which is probably still flying fine, just in a very high-drag regime, causing a large rate of descent.
Also if you decelerate harder into the stall, you can enter a dynamic situation and get a higher AoA before the aircraft responds. If you study unsteady aerodynamics (and I wouldn't recommend it unless you are very fond of higher maths), then you'll see that pitch rate actually will affect the stalling AoA, and with a high deceleration rate (actually rate of increase of AoA), you'll get some very low stall speeds.
Not sure of a any other book on the subject, but I'd start with Darrol Stinton's "Flying qualities and flight testing of the aeroplane", very expensive but unbeatable in the English language for it's subject coverage.
G
Last edited by Genghis the Engineer; 5th August 2002 at 20:08.