Commercial Fixed Wing
Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP)
Situational Awareness; Human-Machine Interface
Deviation / Discrepancy - Procedural Published Material / Policy
General None Reported / Taken
Aircraft; Human Factors; Procedure; Manuals
I am writing this report in regard to the current wording in applying takeoff thrust with or without auto-throttles armed. Paraphrasing the AOM in setting the takeoff thrust with auto-throttle; a pilot will advance the throttles to approximately 40%; wait for the engine to spool up and then promptly advance the thrust levers while simultaneously selecting TOGA (Take Off Go Around); and then monitor thrust lever advancement. For manual setting the thrust; the stabilizing of the engines is omitted while the rest stays the same. My safety concern; from my experience; is that a number of times in promptly advancing the thrust levers and simultaneously pressing TOGA button results in the auto-throttles getting confused and entering the ARM mode in the FMA (Flight Mode Annunciator) while the thrust setting is essentially set manually by the PM (Pilot Monitoring). In a few cases; this procedure resulted in taking off with more thrust; less thrust and/or asymmetric thrust setting due to the PM failure to monitor the auto-throttle mode being in ARM mode and not N1 mode. Therefore the current procedure results in the takeoff thrust not being set properly.[I'm suggesting] a simple modification to this automatic setting as well as a manual setting of the takeoff thrust is the following. The PF (Pilot Flying) advances the thrust levers to approximately 40% N1; waits for the engine to stabilize at that setting; after which the TOGA button is pressed. At that point the PF will follow (not put forward pressure movement on the levers) the advancement of the thrust levers to their appropriate takeoff thrust setting and calls for 'set takeoff thrust.' The rest of the procedure stays the same. In not interfering with the movement of the thrust levers; the EECs (Electronic Engine Controls) will properly apply symmetric thrust all the way to the programmed thrust setting. The PM has the same job as before; however there is a reduced chance for the auto-throttles engaging in the wrong mode. In addition; the manual setting of the thrust level without the auto-throttles remains the same; 40% stabilized; press TOGA; and now the PF will manually advance the thrust levers and call for PM to set the takeoff thrust. The procedure mostly stays the same except for following; versus advancing the thrust levers with auto-throttles engaged versus manual setting of the thrust levers.
Pilot reported a suggested modification to crew takeoff procedure when using TOGA to reduce the chance of the autothrottles engaging in the wrong mode.