JC,
Fifteen miles is fifteen miles the aircraft cross section has nothing to do with it.
If I were in a row boat in a river no wind conditions, no power, with a 15mph current how far down river would I be in an hour?
If I were in a riverboat in a river in no wind conditions, no power, with a 15mph current how far down river would I be in an hour?
The principle is the same with an airplane. It can also be described in terms of tailwind or headwind.
If we are going 200mph and we have a 50mph tailwind whats our ground speed and how far would we travel in an hour? Remember we are in an airmass when you answer!
Now change that to a headwind we have an airspeed of 300mph with a 100mph headwind whats our groundspeed? We would travel how far in an hour?
Samething as the example of a 15mph direct crosswind. Your going to be off course 15 miles if not corrected.
JC, my calculations are that with a trad bow shooting at the 180fps in a 15mph X-wind shooting at a 20yd target the drift would be about 7.33inches in the .333 seconds it takes to get to target. With the 4mph crosswind the drift would be about 2" at the same distance same bow setup.