Clandestino posts:
Switching off the autothrust does not take away any of the protections. Holding AT disconect for 15 seconds disables ATHR for the rest of the flight and disables alpha floor only.
As English is not my native language, would you please confirm if I understood you correctly that you advocate fiddling with throttle levers while keeping the autothrottle on. Thank you.
Switching off the AT takes away Vgroundmini, allthough i don't like it, it's still a form of protection. More importantly it takes away the very original action of the AT, meaning that it wants to fly the manged/selected speed or Vls and intervenes BEFORE Aprot. I would also call this a form of protection.
As to your "fiddling" coment. I suspect you have never flown a modern moving AT/throttle system i.e. on a 744, 777, MD11. The characteristic of a Heavy, beeing basically more stable in terms of speed, however beeing slightly more vulnerable once in a speed deficit (harder to get out), you would appreciate the coordinated effort of a AT with the pilot. At least i would not call this symbiose "fiddling". The AT has different sensors to mine, the latter sometimes superior to his and vice versa.
What i said is that having the AT engaged, it will aim to fly the managed/selected Va, switched off it will only prevent the aircraft to go below Vs (minus some design tolerance) or A prot. So with AT engaged, flight is slightly safer and more comfortable. I further stated that beeing capable of intervening, or overriding a engaged AT, leaves more options to the pilot as either having to rely solely on the AT or, in case of performance doubts, disengage it. He can momentarely intervene, just to let the AT continue once the intervention is over.
You may call it fiddling, but i strongly believe that, with the same protections and performance, a moving AT where the pilot can assist or interfere, is safer than a fixed one where he can either only observe or disconnect.
GMDS
Last edited by GMDS; 25th Mar 2007 at 07:42.