737 - A/T take-off procedure (Merged)

[A37575]

There never was a Boeing published requirement to verbalise "Stabilised." Both pilots have eyes and all that is needed is to observe- not talk about it.

[Elixir]

When should the thrust be set by though? I thought it was 60knots, in which case it is often necessary to intervene as the AT second stage is sometimes too slow to reach target by this speed. A couple of times I've still been waiting for the thrust to set when we've reached 80knots - and in my company we are supposed to have "thrust set" before we call "80 knots".

EDIT: Check posts #4 and #13 in this merged thread.

[Boeing Pilot]

According to my knowledge the "Thrust set" call should be made when N1 at T/O thrust is -0% to +2.5%.
Another important issue regarding setting thrust is that if you're on a slippery rwy and hit the TOGA switch before N1 is at least 40% or if the T-levers move upp unequally you will if you're unlucky veer of the rwy.

[I-2021]

Originally Posted by BOAC

Lucky strike! Boeing Flt Ops Tech Bulletin 737-300/400/500 97-1 Dated April 29, 1997. ATA Number 22-31 Subject Autothrottle Operation. from Flt Crew Training PO Box 3707, Seattle.

Precised: First stage is to within 8% of target N1, then to target. THEN (and only then) pilots should adjust to +1% -0% of target. Avoid applying force to the levers unless manual intervention is intended. It also recommends NOT 'following' the levers such that you apply more than 1.5 lbs of force at the top or you may cause the clutch to malfunction. There is a 'caution' that more than 20kts of headwind may produce throttle hold before target is reached.

I always maintain the autothrottle should be allowed to TRY to set power or you may never know when it is malfunctioning.

Hi BOAC,

After having read this one I understand the following :

1)When the PF asks for T/O thrust and pushes TO/GA, the PM is not supposed to follow the thrust levers to "adjust" them to the desired N1 value until this value has been reached, or as stated in the FCTM, if THR HOLD occurs before 84 kts (or 64 kts for my dear old originals ).

2) The CM1 (usually the Captain) should be waiting the thrust to be set at the desired N1 value before placing his hands on the thust levers.

Is that the meaning of the bulletin ?
Thank You

[BOAC]

Not quite, in my mind, anyway.

It also recommends NOT 'following' the levers such that you apply more than 1.5 lbs of force at the top or you may cause the clutch to malfunction

- the main thing is to stop the NHP 'fiddling' with the thrust levers because they do not go straight to TOGA. Very common in my last airline as a lot of the F/Os did not seem to understand the Boeing a/throttle system, giving the levers a 'shove' when they hit the first 'set'; normally going OVER TOGA at which point the a/t comes back a big chunk, and if throttle hold sets in then you can be 'short', resulting in the wrong T/Off N1 at throttle hold. It also masks u/s clutches etc because the system is not allowed to operate correctly - so you may never see the 'failures'. Better in my current airline as the Captain ALWAYS handles the throttles after button push.

Nothing AFAIK to stop anyone 'following' the levers (in fact a good idea for me) - just do not fiddle with them until you have to! Hands rested lightly on top is my method.

[I-2021]

Originally Posted by BOAC

Not quite, in my mind, anyway. - the main thing is to stop the NHP 'fiddling' with the thrust levers because they do not go straight to TOGA. Very common in my last airline as a lot of the F/Os did not seem to understand the Boeing a/throttle system, giving the levers a 'shove' when they hit the first 'set'; normally going OVER TOGA at which point the a/t comes back a big chunk, and if throttle hold sets in then you can be 'short', resulting in the wrong T/Off N1 at throttle hold. It also masks u/s clutches etc because the system is not allowed to operate correctly - so you may never see the 'failures'. Better in my current airline as the Captain ALWAYS handles the throttles after button push.

Nothing AFAIK to stop anyone 'following' the levers (in fact a good idea for me) - just do not fiddle with them until you have to! Hands rested lightly on top is my method.

Thanks a lot BOAC ! That is in fact what I usually do and seems to me also the most logical course of action