Denti: Wrt:
Actually, the 737 uses reduced thrust for G/A. At least as long as you only press the TOGA buttons once.
Err, yes & no, wherein what you've stated is not exactly how it works (and being that the two-engine go-around in the B737 is one of the most balls'd up manoeuvres, I hope you won't mind if we dot the I's and cross the T's on the matter?!)
A single press of the TOGA button will command an N1 that would provide a reduced level of thrust for a go-around, but only on the assumption that the pilots then move the thrust levers to match the demanded N1 (
that is unless they're doing a dual-channel approach with a functional Autothrottle; or unless they're utilising the 'Autothrottle ARM mode' ?).
On that latter point, some airlines allow (
and / or require) their pilots to fly an approach using the 'Autothrottle ARM mode' (
a procedure which is also sometimes referred to as 'Speed Off' mode) and wherein, to cut a long story short, the principle behind that 'Autothrottle ARM mode' is that, the pilot can move the thrust levers at will with the Autothrottle in 'ARM' but, on the press of a TOGA button, the Autothrottle will re-activate and automatically advance the thrust levers to the relevant N1 thrust position (
the demanded amount of N1 being based upon whether it was either one or two presses of the TOGA button... and / or also inject some thrust if the speed generally gets too low during the approach), BUT... and this is an important 'BUT'... that 'Autothrottle ARM mode' procedure is not recommended by Boeing (
see also the Boeing B737 NG FCTM: Autothrottle ARM Mode; and there was also an FCOM Notice of Errata Bulletin about it too... though for the life of me I can't seem to locate it?!).
And, fwiw, amongst some of the other reasons that Boeing don't recommend the use of the 'Autothrottle ARM mode', is because the Autothrottle can come in too aggressively, i.e. when the TOGA button is pressed (
especially relevant if it is re-activated when close to the ground, i.e. thus risking of a tail strike... which apparently has happened, so Boeing say), and that an Autothrottle malfunction (
particularly a failure to advance the thrust levers) when the TOGA button is pressed would see a FD demand a pitch increase but without a corresponding increase in thrust (
i.e. if the pilots were relying on the Autothrottle to move the thrust levers?!).
Needless to say, with a single-channel approach and / or manually flown approach (
with both assuming that the Autothrottle is fully switched off), a click of the TOGA button will not advance the thrust levers automatically, but it will command the N1 bugs to an appropriate thrust demand... a demand which the pilot(s) can then match via manually moving of the thrust levers, and which will then attempt to give the desired rate of climb that you describe, based upon the number of TOGA button presses (
as you describe).