"Clark W. Griswold, Jr." wrote in message
...
Bob Noel wrote:

The chokepoints are the airports in the US. Freeflight isn't going to be
much
help in the US.

The chokepoints are a handful (less than 12) high volume airports. Those
airports are high volume primarily due to the hub connections through
those
airports. Eliminate or reduce the hub traffic and those airports are much
less
likely to be choke points.

Clark, I'm an instrument-rated pilot so I know how "the system" operates.
There's a lot more to it than archaic technology, though that certainly
plays a role.

There's a number of things you need to consider. First, we're not talking
about reducing the overall volume of traffic-far from it. In extremis,
you're replacing one 757 with three or four RJs and a dozen microjets. For
the most part, it places just as much of a load on the system to move one
6-seat Citation Mustang as it does to move that 757. So "reliever" airports
(the secondary fields within 50nm of the big airports) are only providing
relief until they start having a critical volume of traffic, at which point
they become just as big a chokepoint.

Second, you need to consider the seriousness of what we're fooling with
here. The need for safety should be obvious, and we know our current system,
clumsy as it appears, in fact provides outstanding safety. Australia? Big
deal. They've got the landmass of a third of the US and maybe 5% of the
traffic volume. Ask any air traffic controller and they'll tell you "Free
Flight" works great so long as you don't have that much traffic to handle.

The single biggest problem with free flight is that without extensive
reliance on computers, it simply can't work. Even a dozen of the best
hotshot center controllers can't handle fifty or a hundred aircraft on
random routes. In the current system those dozen people can handle a lot
more planes, even if the radar goes down. Then there's weather to think
about: the minute the thunderboomers show up everyone's going to start
diverting around it. Again, you can't manage this without computers. There's
simply no way for humans to resolve all the potential conflicts, and even
with computers this is going to be messy. This is placing an absolutely
enormous amount of faith into something with so many points of failure. Just
look at those computer failures at Comair over Christmas and imagine if
those were running the live ATC system. Scary stuff.

Free Flight is not an incremental step--it's a complete change of doctrine
and I don't trust making that kind of leap. I've seen companies with far
smaller and simpler problems screw up technological transitions of far
smaller complexity. How many errors can we tolerate before we get it right?
There's plenty wrong with the FAA but when you get down to it they are
probably one of the most competent of the federal bureaucracies simply
because the public will not tolerate failures when the mistakes are counted
in dead bodies. The Department of Education can swallow billions with
nothing to show for it but if two 737s collide it's going to be front-page
news for a month. None of this airspace-managemt stuff is theory- it's 100%
practical knowledge gained in the school of hard knocks and not to be
dismissed as simply "highways in the sky."

Best,
-cwk.

PS- If the subject interests you, a Center Controller in Atlanta writes a
column on a site called AvWeb that often touches on this subject. His
opinions are often controversial and many think he's just an old warhorse,
but he has spent enough time in front of the scope to earn the right to his
opinions: a good sample is this one:
http://www.avweb.com/news/columns/186059-1.html