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Old 16th May 2012 | 16:08
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From: EGDC
AnFI - as previously posted, the blade starts to flap down as soon as it passes the 12 o'clock and sees a reduction in TAS so although the min speed over the blade is a 9 o'clock, the increase in AoA has already started due to the flapping.

In normal circumstances, the aircraft pitches up and rolls left but in Fidor's case his roll right might be explained by a reduction in aerodynamic damping at high DA allowing the blade to flap lower and take longer to recover to unstalled flight. It doesn't do this at 'normal' DAs.

Remember that from the 9 o'clock to the 6 o'clock the blade is seeing increasing TAS until at the 6 o'clock it has the same TAS as at the 12 o'clock so recovery (in normal DAs) is unlikely to be anywhere past the 6 o'clock.

As I said before, high DA affects the Lock number which affects the phase lag - I suspect Shawn or Nick can confirm this and whether or not it could be a causal factor in Fidor's observations of a right roll during RBS.

Last edited by [email protected]; 16th May 2012 at 16:11.
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