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Old 25th May 2011, 15:31
  #2367 (permalink)  
Join Date: Nov 2006
Location: SoCalif
Posts: 898
from Aero Caraibe report:
At 22:22:59, a very rapid decrease of CAS, of mach, and of altitude (correction of mach). The parameters changed respectively from 273KT to 85KT, MO.80 to MO.26 and altitude from 35,000FT to 34,700FT. At the same time, the FD1&2 and I'AP2 disconnected...

Shortly appeared six ECAM messages: F/CTL ADR DISAGREE; F/CTL ALTN LAW; F/CTL RUD TRV LIM FAULT; AUTO FLT REAC W/S DET FAULT; ENG1 EPR MODE FAULT; ENG2 EPR MODE FAULT. Each message was accompanied with MASTER CAUTION and a SINGLE CHIME. Also, the SPD LIM RED FLAG appeared on both PFD.

At 23:23:36 (their typo) and at 22:23:45, STALL was broadcast over the loudspeaker. It was accompanied by the CRICKET and illumination of MASTER WARNING.

From 22:23:00 to 22:23:54, the value of TAT diminished(?) to -14C.

AT 22:24:25, the CAS increased from 111KT to 275KT, the mach returned to initial value of MO.80 and the altutude increased quickly from 34,200FT to 34,500FT.
Note: You are welcome to correct my translation, as Spanish is the closest to French I can do.

It's obvious from the above that it was the ram tube that clogged, and the drain remained open, causing the quick decrease of airspeed. The clogging was less than 90 seconds duration. Would a longer clog time have mattered?

If the clogging had been more gradual, would the drop in sensed altitude cause the A/P to command Fly Up, rather than disconnect, and would further clogging cause lower sensed altitude increasing pitch up to the point of a real stall?
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