If NADP1, we'll fly that. If NADP2, then that is what we'll do. If nothing is stated, then 400'.
Is that a thrust reduction at 400 feet? Sounds low to me, but I can't remember all that stuff about the fifth segment climb gradient. Maybe 400 feet is the minimum for the thrust reduction in the regs but seems like everywhere I've worked we used something like 800 or 1000 feet for the power reduction on the more fuel efficient (and noisier) takeoff profile.
Dare I say it, but that smacks of a fix-all SOP in the absence of truly understanding the individual local requirements? ie. The most limiting (apparently), would be NADP1, and so let's adopt that as our standard.
We do NADP 1 in the UK and Europe for simplicity. It seems to satisfy the requirements for the noise folks at every airport we go to over there. But there is already talk of changing it to something else to save the whales.
In America we figure that simple procedures are best and the most likely to be performed correctly. I realize that some other cultures seem to thrive on infinite detail.
You can get some idea of the cultural philosophical differences by comparing the airport reference pages at LHR and JFK.
Don't know if you fly to NRT but the NADP 1 takeoff profile is still in the reference pages. It's a lot easier for a country boy like me to understand than the LHR writeup about them dBA's and the 4% climb gradient.
