Previously I mentioned this column by Salon's "Ask the Pilot" writer Patrick Smith, which laid out the fundamental reasons U.S. airline flights run into so many "unexpected" delays.

Here is another clear, logical, and authoritative explanation of the obstacles that simply aren't going to be removed by any of the frequently-discussed "solutions" to airline congestion. (Including the totally bogus idea that "opening up" military airspace would make any difference.) What would make a difference? Well, you'll have to read it for yourself and see.

This latest account comes from Don Brown, long-time air traffic controller who now writes his "Get the Flick" blog about aviation. It's long, but it's clear and interesting. Here's a hint about its point: if a runway can handle at most 60 planes an hour, and the airlines schedule 70 for that same hour, the planes will be late.

Airlines can make more money selling 70 airplanes worth of tickets per hour than they could if they limited themselves to the 60 airplanes per hour that the runway can handle. In fairness to the airlines, it’s not in their interest to limit themselves. It is easier to sell the tickets and blame the delays on the weather or the “antiquated” air traffic control system. Especially if the flying public doesn’t understand runway capacity limits and therefore fails to notice that the “antiquated” air traffic control system is delivering more airplanes to the runways than the runways can handle.

More here.

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