"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.