PPRuNe Forums - NADP Takeoff thrust time limit

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Quote:

Originally Posted by RandomPerson8008 (Post 12026631)

Ok, thanks, so it seems you all are suggesting that the airline may have made up the ICAO/NADP 3,000 ft takeoff limit as well as the initial 3 minute supposition. I understand the airline doesn’t want the engine in takeoff thrust for any longer than necessary for engine reliability. It seems like that alone would be a good enough reason to select CLB thrust when they want us to so I’m not sure why we needed to go through all of this. Thanks for everyone’s help, I’ll go back to radio silence.

The home carrier routinely operates B744/B748 at MTOW out of VHHH, and has done so for nearly 30 years now.

Just like Giant and UPS their standard B744/B748 NADP2 profile is ACCEL: 1000 AGL, THR RED: F5.

When heavy, the 210kt restriction delays flap retraction and therefore thrust reduction at F5. SOP has always been to set THR RED: 2500 or press THR on the MCP when passing 2500’ AGL.

Quote:

Originally Posted by RandomPerson8008 (Post 12026197)

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.

Hello RP:

This is from an Airbus manual, but since NADPs characteristics do not depend on aircraft type, I guess this might help:

https://cimg3.ibsrv.net/gimg/pprune....cda0982b33.png
I suppose your query is about a NADP 2 profile. Most airports I'm familiar with use NADP 1, but I've been to some (Vancouver, Canada, for example) that use NADP 2. At these NADP 2 airports, my last operator also wanted us keep TO thrust above thrust reduction altitude and, at about 3000ft, accelerate and clean up, setting climb thrust (and the packs!) after the first flap retraction. I take it that 3000ft is the "upper limit" as far as NADP profiles go, hence the 3000ft figure you lot are being handed by your company?

Quote:

Originally Posted by Escape Path (Post 12027225)

but since NADPs characteristics do not depend on aircraft type, I guess this might help:

Don't they? From reading this post it seems there are a lot more interpretations than the two I learned!