Performance : V2 and Vmca
 

Hi,

Could someone explain that one :

Question : In certain conditions V2 can be limited by VCMA:

Right answer: Low take off mass, large flaps extension, low field elevation.

I believe I understand the answer except for the "Large flaps extension".
Does anyone have an explanation for that ?

Thank you,
Emmanuel.

Because V2 can be limited by the higher of 1.1 VMCA or 1.13VSR, if flaps are extended 1.13VSR is lower and therefore the 1.1VMCA limit is more likely to be controlling.

http://img97.imageshack.us/img97/121/130166.png

Its interesting to note that V2MIN must also not be less than VR plus a speed increment attained before reaching 35ft. When the aircraft is very light and accelerating quickly this can cause higher values of V2MIN at the left hand side of the graph. I've left it out here for clarity.

Ok, it makes sense.

Thanks a lot.
Emmanuel.