V2 is basically constant for flap setting and weight.
So think of it this way, if V2 for whatever weight and flap setting is say 150kts.
And using TO2 say for arguments sake VR is 140kts, after rotation you end up at 160kts (V2+10).
If you use TO1 and rotate at 140kts you may end up at say 170kts. (V2+20).
And Max TO at say 180kts (V2+30) after rotation therefore VR is reduced with the aim that you finish at V2+10 all the time.
Obviously minimum speeds must be respected so VR can only be reduced so far before you result in getting VRmin. (1.05 x VMCA)
Last edited by CCA; 6th Apr 2015 at 05:32.