V1 Refrence
I'm sure there is a perfectly reasonable explanation, but I haven't found one...
Why does V1 use IAS rather than groundspeed. If it is to do with stopping distance, then surely the airflow over the plane has little effect on it. If you had a headwind, then you would reach V1 at a slower groundspeed than with no headwind, so you would have 'more runway' ahead of you stop in.
Or is it simply a case of groundspeed is IRS derived, IAS is from a pitot tube?