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Old 20th Mar 2015, 21:51
  #32 (permalink)  
BARKINGMAD
 
Join Date: Mar 2007
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TEST FLYING ON REVENUE FLIGHTS?

"How about a few out there on this thread actually try this at TOD and then post back on this thread what the result was. Reduce power, pitch up slowly to avoid a climb and then get back to us. Try for flights below at and above optimum. It is deemed to be safe so there should be no issues. It will be interesting to hear the results."


And if something out of the ordinary occurs "it will be interesting to hear" the subsequent interview with fleet/flight manager(s)!!


Whilst I appreciate the desire for some HARD info on this topic, I doubt whether a line sector is the place for such research by ordinary line dogs.


However, it reinforces my oft-voiced opinion that the particular type simulator is NOT the realistic tool we are all sold by training and management.


Post AF447 when still practising the art, I made sure I knew with instant recall what pitch/power/trim my craft was using to survive at the cruise mass at the (aerodynamically dodgy) cruise altitude, where, when things go wrong, they go wrong quickly.


The 73NG seemed to be happy with the rule of 3s, namely 3ish degrees pitch, 90% N1 and 6.0ish on the stab trim. The cruise N1 was usually a bit less than 90, but if the wind powered instruments go AWOL, then I think I'd rather go too fast than risk slowing and reducing my energy and risking stalling. I am convinced this type, at cruise mass/altitude, will inevitably slow down with 75% N1 and would not be happy to go there.


Thank you Mr Boeing for doing some work on this, but you are the organisation who recommends I select Eng Anti-ice ON plus Airframe Anti-ice ON, above FL350, if I run into volcanic ash??!! Those of you on the type might like to imagine the resultant chaos if/when the dual bleed trip occurs as you are trying to sort out the Ash Encounter procedure!!


Still have not had a satisfactory answer to this one, and I'm NOT pretending I'm cleverer than their TPs, but here is a QRH item which directly contradicts the recommendation in another QRH, so I and others are left with a certain lack of confidence in some published procedures. And yes, the lawyers would have a field day, but if I'm still alive to argue then so be it.


Tin hat at the ready..........
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