Not sure how to get to the airport as we had a car, but the spots are extremely close together and can be used whichever runway direction is in use. As you suggest, they are all located on that stretch of beach.
A word of warning though - any images you see online taken in or before January 2011 will not suffer from the new perimeter fence, which was actually being erected during my visit. Luckily it wasn't completed until our last day but it makes some spots way more difficult to get good shots from.
Also, we found it a quiet place, with not much variety. Still, worth bobbing along if you're in the area on holiday. The beach has a very 'St. Maarten feel' (although not as good obviously!).