Performance wise, I wonder if any serious problems arise. For the 737NG (700W) the V2 numbers (at 55T or 115K lbs) don't seem to vary:
(i) from max assumed temperature reduction (25%) D TO-2 at 60 deg AT, to RATED TO-2 thrust, the V2 remained virtually identical.
(ii) from FULL DERATE-2 (20K) thrust, up to MAX RATED (24K) thrust, the V2 remained vitually identical.
At limiting situations (Obstacle, Climb) there wouldn't be much of a difference between the flex thrust, and rated, I would think.
And in contaminated/slippery runways, there's no flexing.
I did note, for the NG, it would be possible for Vr to be 2 knots less than V1, using your 'advice'.
What are the differences in speeds we are talking here?
Trying to improve on the approved methods, seems unnecessary. (Like brake stands to improve short field takeoff).
So, what's the purpose?
Last edited by jonny dangerous; 4th Nov 2007 at 21:46.
Reason: additonal 'Talking Points'