I suspect that at least part of the problem stems from the fact that the non-stop Philadelphia to St Martin flight is now operated only once a week, instead of on a daily basis, in season. Demand exceeds capacity.
Also, American Airlines flies an Airbus A-319 on this route. In the old USAirways days, USAir operated a B-757, which was a larger aircraft. Also, the B-757 was able to clear the mountains at the end of the runway, after takeoff. While it was after dark when we finally took off for Philadelphia for the return flight, I am pretty sure that our plane took off 'backwards"; that is to say that we flew over the beach and water after takeoff.
With rising jet fuel prices, I don't think that the airlines will operate any flight unless the plane is almost full.
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