PPRuNe Forums - View Single Post - AF447 final crew conversation - Thread No. 1
Old 18th Oct 2011, 11:43
  #175 (permalink)  
Gretchenfrage
 
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Very good link indeed AZR.

I guess the pilot's statement says it all.

What is even more compelling, is the continuation of this recommendation:

Another approach may be to incorporate “hard limits” with a pilot override capability such as an “instinctive cut-out” switch. Or alternately, the CFIT recovery capability on the 777 could be enhanced if the aircraft’s Primary Flight Computers (PFC) were design to recognize aggressive pilot inputs as a desire for maximum aircraft performance. The PFCs would then provide maximum pitch rate consistent with AOA or g limits (depending on airspeed). If the resultant aircraft performance was not sufficient, the pilot could then pull to the full aerodynamic capability of the aircraft. Additionally, automatic speed brake retraction, in the event of a go around or CFIT escape maneuver, should be provided in the 777 design. This system although somewhat complex mechanically, can be implemented since the PFCs will control any undesired pitch excursions.
I have repeatedly asked for such a cut-out switch on Airbus.

A little further away from CFITs, there are the two recent 0 power (or almost 0 power) accidents: Hudson and LHR.

It has been fastiduously pretended, that Sully only could succeed in putting his 320 on the hudson, due to the Airbus FBW. I believe if you can do that with a Cessna or a 320, it is just as much possible with a T7. The Aethiopian might have succeeded, if the thug was not strangling the pilot.
So no advantage to AB-FBW here.

I just wonder now, if with a 330 the LHR accident would have been as benign. Didn't the pilot oversteer the impending stall to reach the runway? In an Airbus this would have been inhibited .....

Again, to me the, although as stated "subjective", the verdict of the test pilots clearly says it all.

Airbus might simply consider to implement that cut-out switch! Their version consisting of a bulletin to tell the pilots to switch off two Prims and one Sec, is not practicable, allthough basically admitting, that such a possibility is necessary.

Who knows, it might have helped on AF447
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