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Thread: UK F-35B Lost
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Old 1st Dec 2021, 11:30
  #254 (permalink)  
aeromech3
 
Join Date: May 2011
Location: Surrey UK
Age: 75
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I had resisted questioning the hypothesis that an engine intake blank was missed in the preflight: from my experience which includes civil versions of military jet engines: I would expect there is FADEC on the F-35, then during start, an over temperature, EGT, would have been avoided, but it would be in the high region and doubtful the FADEC would have continued the start; typically due the lack of mass airflow the N1 and N2 speeds would rise quickly and even if this blank only caused a partial airflow blockage, the engine would undoubtedly surge (reversal of airflow) before reaching any power level to commence a take-off roll.
I propose a loss of a sensory input to the FADEC such as that normally created by forward velocity is more likely, possible some pitot type blank/plug would have limited the engine thrust during the roll; an instance I had to investigate due an aborted take-off was post a fuel control change on an RB211, the rubber gasket of a transit blank had been inadvertently missed, for a sensor pipe connection and, as the post FCU change only called for a flight idle run it was not until the aircraft started its take-off roll, that the engine failed to make take off EPR.
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