pakeha-boy,
Lousy timing, I'm on the way out the door to some freedom loving people's republic of something or other.
If the paper figures that you refer to are Airport (Runway) analysis speeds, go with them, you may have an unbalanced field.
Tailwind uses 150% of wind component, Headwind uses 50%, the computations are different.
Mutt and John_T can come up with much much more.
The revolutionaries await.....................
Best Regards,
Old Smokey