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Old 11th Jan 2010, 10:56
  #5972 (permalink)  
walter kennedy
 
Join Date: Sep 2003
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HamishMcBush
<<...back in the 1990's I worked for a company that was involved in the FADEC software for the Chinook in question. I was told that immeditaley prior to the crash, the demand had been given to both engines for maximum power (and lift too?) but they had not responded to the pilot's request. ...All that is clear is that the instructions given by the pilots did NOT get translated into commands to the engines. To blame the pilots for this crash is therefore WRONG 100%....>>
You would have had the processing delay of the FADEC system and then the turbine lag to be overcome before the demand came into effect – as it would appear that the final extreme control demands were only made in the last ~3 secs before impact, then you cannot draw the conclusion that the FADEC was at fault in not translating the demand.
It would be of interest to all readers here if you were to ask your (then) colleagues to quantify what the expected FADEC processing delay would have been back then – don't forget to factor in that the FADEC would have been (before those last seconds) reducing fuel to reduce RRPM as they had been slowing down (in terms of TAS from waypoint change to impact site according to Boeing's analysis) and thus the rotors would have been tending to pick up RPM as the drag reduced – how responsive timewise was the FADEC system to changing processes?
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