A380 unveiling, 1/18/05, Live.

"Colin W Kingsbury" wrote:

Why won't we all fly microjets? First, fuel is going to get a lot more
expensive, and microjets are not by any measure fuel-efficient. We're not
finding many new reserves and one billion Chinese are just beginning to
discover the wonders of automobile ownership. Most of us will have a hard
time flying a 172, let alone an Eclipse, when fuel costs $6-$7/gallon in
today's dollar.


This argument is semi-legit. I say semi, because noone really knows what will
happen with energy prices in the future. As new energy sources are put online,
the value of the older ones (like oil) will tend to stablize.

Second, the air traffic system simply will not be able to handle it. There
is very little scalability left in the current system and microjet
proponents are talking about doubling, tripling, even quadrupling the number
of planes in the system. The current ATC environment was grown organically
over the course of nearly half a century and I just don't believe that Free
Flight or anything else can squeeze that many more airplanes into the same
amount of sky. Frankly we'll be lucky if we can just keep the current mess
from collapsing in the next decade.

This is a common misunderstanding and reflects a lack of knowledge about how
commercial aircraft fly, how big a domestic airspace the US has and where the
chokepoints are.

Our current ATC system is built around virtual highways in the sky. It can't
deal very well with traffic that wants to directly from point A to point B.
Instead, traffic going into / out of /between major cities is funnelled into a
small number of very specific tracks.

While that's not the most efficient use of airspace or fuel, under normal
weather conditions the only bottlenecks are those handful of large city
ariports. Microjets aren't intended to fly you from ORD to LAX. They're designed
to pick up that out city passenger and drop them off at another out city.

Bad weather is more of a problem, as that can close some of those virtual
highways in the sky, but it tends to be localized around a certain area. Getting
around it funnels more traffic into lesser routes, slowing things down a bit.
Micros will be able to fly a bit higher than standard commercial aircraft which
will help a bit (think 3D), but still will add some congestion.

The way around that is the relatively slow conversion from the current airways
based system to a more direct point to point system. The current planes have no
problems doing that, but upgrading ground ATC computers is taking a long time in
the US.

Other parts of the world (like Australia) have completed the upgrade and have
much more flexibility to direct route aircraft. Eventually the US will get there
as well.

In article ,
"Clark W. Griswold, Jr." wrote:

[snip]
This is a common misunderstanding and reflects a lack of knowledge about how
commercial aircraft fly, how big a domestic airspace the US has and where the
chokepoints are.

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

--
Bob Noel
looking for a sig the lawyers will like

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.

Freeflight doesn't help directly with approach or departure contraints, but it
increases the options for getting planes away from an airport and combined with
point to point service (either RJ or microjet), helps indirectly spread the
traffic out.

"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

On Thu, 20 Jan 2005 06:16:42 GMT, "Colin W Kingsbury"
wrote in
et::

The single biggest problem with free flight is that without extensive
reliance on computers, it simply can't work.

Today the STARS system
http://www.faa.gov/ats/atb/Sectors/Automation/STARS/ is currently
being deployed in the US. STARS provides updated computer technology
for approach and terminal phases of flight. ERAM
http://www.faa.gov/aua/enroute/index.cfm?fuseaction=home.products&page=detail&pro dID=1
architecture replaces the current aging, and soon to be unsupportable,
en route system while providing all of today’s functionality and
adding the new capabilities needed to support the evolution of the
NAS. It will begin being deployed in 2006. So the FAA is addressing
the issue as we speak.

"Colin W Kingsbury" wrote:

Free Flight is not an incremental step--it's a complete change of doctrine
and I don't trust making that kind of leap.

You are absolutely right. Certainly the concerns you identified are real. One of
the things I do is design avionics for large aircraft, so I'm in the middle of a
lot of the discussions on how to manage the transition, which has to be
evolutionary - not a huge leap.

In article ,
"Clark W. Griswold, Jr." wrote:

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.

But without more runways, there will only be so many aircraft that
can be launched and recovered...

--
Bob Noel
looking for a sig the lawyers will like

On Thu, 20 Jan 2005 07:39:04 -0500, Bob Noel
wrote in
::


But without more runways, there will only be so many aircraft that
can be launched and recovered...

Most runways in the US are vastly under used today thanks to the
airlines' reliance on hub-and-spoke architecture.

"Bob Noel" wrote in message

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

--
Bob Noel

That is one opinion. Others have just as much value.

Point to point will let the "hoard" of VLJ's fit in to the small airports,
which should relieve some of the pressure off the big airports. They will
also not have to arrive at the "big push" times at the major airports.
--
Jim in NC

In article , "Morgans"
wrote:

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


That is one opinion. Others have just as much value.

All opinions have the same value? Would an opinion based on
incorrect data have the same value as one based on correct data?


Point to point will let the "hoard" of VLJ's fit in to the small airports,
which should relieve some of the pressure off the big airports.

why aren't they flying to small airports now? Do you think it's because
of the lack of freeflight in the US NAS?

--
Bob Noel
looking for a sig the lawyers will like