View Full Version : autothrottle during takeoff

12-08-2005, 12:10 PM

At takeoff the throttles are put into FLEX or TOGA. When reaching the ENG OUT ACC altitude set in MCDU
the PFD will show flashing THR CLB or something to que the pilots to set the throttles in CLB gate. If this is not done,
can you tell me what the N1 of the plane will be?
The reason for this question is that I'm in a discussion with Enrico Shiratti (Project Magenta software) about this.
His software reduces the thrust to 87% N1 at the ENG OUT ACC altitude.

Peter , Belgium

12-08-2005, 05:52 PM
Hi Peter,

Actually is not the Engine out ACC altitude is just the Acceleration altitude the acceleration altitude on the bus is normally 1500 feet AGL for engine out! So the concept is ACCELERATION ALTITUDE which can be set higher or lower! Ok if you donīt move the throttles to the CLB gate the plane will simply mantain the takeoff thrust either TOGA or FLX thrust which ever was selected, simply cause when you put the levers on the CLB position you ENGAGE the Autothrust before that you only ARM it!! It will not engage until you move the Levers to the CLB detent!
It shouldnīt reduce the power at ACCELERATION ALTITUDE cause the Autothrust is not engaged it is just armed! So it shouldnīt be doing that!