Re: Analysis from a JHU CS Prof

[John Fraizer <nanog () Overkill EnterZone Net>]

On Wed, 12 Sep 2001, David Howe wrote:

> > Also, it's worth remembering that airplanes aren't all that easy to
> > fly. This means that the perpetrators needed to find five adequate
> > pilots,
> Hmm. not actually sure about this - not having ever flown anything at
> all, but how much skill exactly does it take to keep something already
> pointed in more or less the right direction on target for two-three
> minutes until impact? ok, you couldn't expect a clean landing or even a

It takes quite a bit more than you would expect.  Something that you
neglect to remember is that the plane that struck the Pentagon was
initially headed directly towards the Whitehouse, then executed a
high-speed, high-bank turn around DC, lined up on the Pentagon and managed
to nose into it at mid-level.

It is VERY difficult to control an aircraft in a high-speed nose-down
attitude.  ESPECIALLY those that are less than "sporty" in flight
characteristics.

> halfway-smooth flight path from someone who has played a MS-Windows
> flight sim for a few months, but - if he was going from switching off
> autopilot to keeping the plane pointed at something the size of the
> WTC....... I would imagine it would all be on the yoke too, no throttles
> or concerns about airspeed given you are not really going to care that
> much what speed or acceleration you have on impact...

Again.  Think about it.  The WTC is not actually that large of a
target.  Granted, it's was easy to pick out from the air but, lining up on
it and maintaining a flight attitude that will keep you in the air until
impact is a different story.  If you've seen footage of the second plane
impacting, look at the last second attitude correction.  Had the
individual who was flying the aircraft not made that correction, it would
not have struck the building. (At least THAT building.)  Also, airspeed is
very important if you want to keep an aircraft aloft.  ESPECIALLY when you
are pulling turns.  If you're just above stall and try to turn the
aircraft, you don't turn -- you fall.

> ... or train for the two/three more common types, then pick a flight *on
> the day* that actually is flying that type of plane. book seats at the
> last minute (not a problem for domestic flights) or pre-book three or
> four different seats per attacker, and each picks a flight with the
> right sort of plane from the "pool" of available flights.

There are mechanisms in place that would detect this type of
behavior.  (Prebooking multiple flights for the same individual.)


---
John Fraizer
EnterZone, Inc