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Old 24th Aug 2010, 09:42
  #1966 (permalink)  
HazelNuts39
 
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Bogus Vmo/Mmo exceedance

Machinbird,

If the pitot intake and drains are blocked, the pressure rise due to heating depends on the volume of trapped air, which includes that in the tubing up to the pressure transducer in the ADM, and for the STBY pitot that in the pneumatic line up to the STBY ASI on the instrument panel. Wouldn't that difference result in less pressure rise in the STBY system?

If the airplane really reached the buffet boundary at FL384 with a deck angle of 27.8 degrees (see discussion 29th june), I wonder if the alpha protection authority (4 deg of elevator in QF72 report) would suffice to prevent stalling in normal law?

regards,
HN39

Last edited by HazelNuts39; 24th Aug 2010 at 11:39.
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