Originally Posted by
ImbracableCrunk
Let’s say your Vr at your actual weight was 138, but the runway could support a higher TOW of 174k with a resulting Vr of 160.
But, max rotation would be 138+20 or 158.
So rotate at 158 unless you get wind shear before that speed.
A good OPT setup will show you what speeds should be used.
ImbracableCrunk is furthermore correct.
Simply said:
- determine maximum TOW and Vr speed for ambient conditions
- determine actual TOW and associated speeds for ambient conditions
- use no more than. +20kts above actual Vr for adjusted Vr but no more than the Vr for maximum weight