PPRuNe Forums - View Single Post - A320 Positive Static Spiral Stability in Turbulence
Old 18th Dec 2011, 08:21
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rudderrudderrat
 
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Hi Field In Sight,

TyroPicard is correct.

the "positive static spiral stability" occurs only because the disturbance has rolled the aircraft past 33 degrees.
From FCOM 1.27.20. Lateral Control
"If high speed protection is operative, the system maintains positive spiral static stability from a bank angle of 0°, so that with the sidestick released, the aircraft always returns to a bank angle of 0°."

"positive static spiral stability" is to prevent the spiral dive. Simply pulling the nose up may not reduce the speed when beyond a certain bank angle, so a "level the wings" command is made when high speed protection is operative.

Last edited by rudderrudderrat; 18th Dec 2011 at 09:02.
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