Originally Posted by rudestuff;[url=tel:12026186
12026186]Not a 747 pilot so can you explain that again? Are you saying you take off with flap 20 and you can't reduce thrust until after you've accelerated to flap 5? I thought the whole point of NADP was to take off, reduce thrust then accelerate (And if you can't make a restriction, tell ATC)?
The normal NADP-2 thrust reduction point for the 747 at the several operators I’ve flown it with is flaps reaching position 5 aka acceleration through Vref 30+40 then a few seconds for retraction from 10 to 5. . Thrust reduction point can be modified during preflight if desired. However this is the default standard as it comes from Boeing I presume, or maybe my employers all coincidentally settled on Flaps 5. Acceleration height on NADP-2 is normally 1000 ft AFE.
HKG for some reason uses NADP 2 all runways however they have SID waypoint restrictions ~6 miles from the runway that require 210 knots maximum. Flaps 5 selection speeds are usually ~230 at maximum takeoff weight.
If nothing is done, following a maximum weight takeoff, thrust reduction will not occur until passing roughly 4000-5000 ft on these SIDs unless an MCP switch is pressed or CDU entry made at the desired thrust reduction point in flight. There is also a 5 minute takeoff thrust limitation. Yet we are being directed by company to select climb thrust not later than 3000 ft AFE, we are told due to ICAO NADP profile requirements.
I am just asking if anyone has a specific reference for this “not later than” 3000 ft AFE thrust reduction requirement. 3000ft will typically be reached ~3 minutes after takeoff thrust application so the 5 minute time limit isn’t the reason.