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Old 3rd Oct 2008, 11:38
  #2087 (permalink)  
clearedtocross
 
Join Date: Jul 2007
Location: Switzerland
Age: 78
Posts: 110
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single signal path to arm TOCW?

It seems to be agreed in this forum that the single WOW signal did not pass through R2-5 to arm the take off configuration warning system, which in turn would have warned the pilots of missing slats/flaps setting and thus would have avoided the accident.
I wonder why the principle of redundant signals is not being followed for such a crucial warning device. Thanks to the quirks of EASA, my humble old taildragger has recently been equipped with a mode S transponder that must be controlled by an air/ground switch. As the gear is always down and welded, the signal is derived from the airspeed pressure difference sensor instead of wow. If the airspeed is considerably below the stall speed, the transponder is in ground mode. Simple and as cheap as it comes for any aircraft installation under the suspicious eyes of EASA and my national aviation grounding office.
It would be easy to include such a sensor somehow into the logic of the warning system as an additional and independant ground mode condition.
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