  The two somewhat conflicting requirements of efficiency and fairness make
ATFM an unsatisfactorily solved problem, despite its overwhelming importance.
In this paper, we present an economics motivated solution that is based on the
notion of a free market. Our contention is that in fact the airlines themselves
are the best judge of how to achieve efficiency and our market-based solution
gives them the ability to pay, at the going rate, to buy away the desired
amount of delay on a per flight basis.
  The issue of fairness is simply finessed away by our solution -- whoever pays
gets smaller delays. We show how our solution has the potential of enabling
travelers from a large spectrum of affordability and punctuality requirements
to achieve an end that is most desirable to them.
  Our market model is particularly simple, requiring only one parameter per
flight from the airline company. Furthermore, we show that it admits a
combinatorial, strongly polynomial algorithm for computing an equilibrium
landing schedule and prices.
