jt-
My verbal shorthand is what caused some confusion. The MLW in itself is of no signifigance. It is simply that around that weight (and lower) for t/o that the *min* speeds start to come into play. I have made takeoffs as light as 160,000 and as heavy as 320,000. MLW is 240,000 to 270,000 depending on series.
Re: V2 vs. density altitude. If I were more computer literate, I could paste a chart here that will make it very clear. Being unable to do that, I will give a few illustrations:
SL - 15C - 200,000 lbs. V1 Vr V2
Actual speeds 94 111 130
Minimum speeds 120 120 138
3000' -15C - 200,000
actual 97 113 129
min 113 113 130
6000' 15C - 200,000
acual 100 115 128
min 102 102 124
Above this density altitude, the V2 min remains at 124. At the lower density altitudes where V2 min is decreasing with an increase in density altitude, V2 min is limited by Vmca (plus the fudge factor). At around 6000', as the density altitude increases, V2 min remains a constant 124 KIAS. That is where V2 min starts to become limited by the 1.2 Vs speed.
I don't know how this formatting will turn out, but it's the best I can do. This is sure an instance where a picture would be worth 10,000 words. Sorry.
