Originally Posted by
spitfire747
“why backtrack do they have no understanding of aircraft performance. .... idiots “
I think his point here was that the performance was calculated and the aircraft perfectly capable of an intersection departure, so he didn't NEED a backtrack.
By giving yourself more runway you're not invalidating the performance figures, if anything you're giving yourself an extra safety margin.
If you've got a wet runway and a V1/Vr split then a recalc might give you a slightly higher V1 or a slightly higher de-rate. But on a dry runway with a full de-rate and no split I wouldn't bother. V1 can't get any higher and engine power can't get any lower so the numbers will come out the same.