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Old 2nd Jul 2009, 17:25
  #2709 (permalink)  
gonebutnotforgotten
 
Join Date: Aug 2005
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Aircraft in Direct law?

Takata

Are you sure it is as easy to fly as you suggest:

Well, at FL350, the aircraft is flying level and all Airbus are flown in direct law without much trouble (ask Lemurian, it is like a 737). They have even been certified like that, before introducing the various level of fligh envelope protection. Not a single report from any previous freezing incident included the quote: "we were left with an uncontrolable aircraft impossible to be hand flown because A/THR and AP disconnected"...

The preliminary report says (note on page 54):

Note : la loi de commande alternate 2 est une loi en facteur de charge en tangage et loi directe en roulis. Seule la protection en facteur de charge reste disponible. Dans certains cas, les stabilités haute et basse vitesses peuvent également être disponibles.

As I understand it there is no way for the crew to revert to direct law at FL350 (though I gather there are some at low speed). So my previous comments still stand, I wouldn't be confident that my basic handling skills, such as they were, acquired on conventional aircraft, would have served me well on that night. To judge from this thread, not many AB pilots have thought through how they would control the aircraft in this condition, and it looks as if the FCOM doesn't help a lot either.
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