PPRuNe Forums - View Single Post - Jet Engine Out Bank Angle
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Old 26th Feb 2017, 08:48
  #18 (permalink)  
zzuf
 
Join Date: Oct 2004
Location: australia
Posts: 215
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JT
Typically during certification 5 degrees of bank will be used for Vmc determination to achieve Vmc min. More bank (not permitted) will give an even lower Vmc.
Climb performance speed speed is established by sawtooth climbs bracketing a speed range, then performance is measured at that speed. Invariably this is at 0 degrees sideslip, at the bank angle required for zero sideslip. The bank angles you suggest fit with my experience.
The flight test aircraft will have an alpha/beta probe (angle of incidence/sideslip).
In the real world, in some aircraft zero sideslip is pretty easy to pick, in others very difficult without dedicated instrumentation. Pretty well all conventional jets will have zero aileron hand wheel angle at zero sideslip due to normally strong rolling moment due to sideslip. All bets off for FBW, but one could select the flight control page and adjust rudder until zero aileron angle at zero roll rate is achieved, not that this would be in any way practical. Propellors complicate things by prop wash induced rolling moment.
There may be operational reasons for climbing at other than zero sideslip.
Not meant as an egg sucking lesson but to add to the general conversation.
Have fun at AV.

Last edited by zzuf; 26th Feb 2017 at 08:55. Reason: typo
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