The general difficulty of the 9/11 flights

The final seconds of flight exhibited extraordinarily precise maneuvering. The plane came in between the Navy Annex (large rectangular complex of building wings in the upper right) and the VDOT antenna to the left of the Annex. It then proceeded at full throttle across the cloverleaf, clipping lamp posts along the way, and made a final corrective maneuver (not available in the truncated flight data which is missing the final few data frames). One witness told us that he thought the plane had actually bounced off the heliport. He was situated on I395 in a semi truck.

Well obviously the plane did not 'bounce off the helipad' as there is no physical evidence of that.
Not even sure why you would mention that. Is that a "precise" manouver in your estimation?

The rest of your post seems to have you trying to tell us that wherever the plane went and whatever it did was precisely what the pilot intended.
 
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Check out this cement truck driver's incredible driving skills!

Not only does he skillfully avoid the white pickup at high speed, he then skilfully flips his truck on its side, and skilfully slides it directly into the exact same car that was filming him!

I bet if you asked a lot of professional cement truck drivers to replicate this exactly, they would have a very hard time!

All the pilots were doing was trying to hit some very large buildings. Exactly how they ended up hitting them was essentially as random as what happened to this cement truck.
 
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The final seconds of flight exhibited extraordinarily precise maneuvering.

Hetware, this doesn't make any sense to me. Any guidance system apart from an optical one, would be following either an inertial guidance or a GPS track which would automatically negate the need for last minute manoeuvring.

Example: When I fly on an air route at at altitude, my groundspeed is generally around the speed observed by this aircraft. The Flight management system, which uses GPS as the primary means of navigation with inertial guidance mixed in, tracks to a waypoint whilst compensating for changes in magnetic variation and drift encountered along the way. The waypoint can be considered the target. Never, EVER do we get last minute jinking to pass over the waypoint, even at 600 knots groundspeed.

We also do GPS approaches which are hooked up to the autopilot. They happen at much slower speed but the result is the same; smooth approaches, which includes a vertical profile, that automatically adjusts for wind gusts. This in a system first certified in 1994.

To my mind, this last minute manoeuvring conclusively points to a human pilot with a Mark One brain whose attention was fully outside the cockpit and unable to register the changes in wind speed or his own aiming point quickly enough to fly in the same way that computer guidance can.

UA175 did exactly the same thing when the hijacker became aware of the drift from the crosswind with less than a mile to go before impact. A computer guidance system would have smoothly compensated for the crosswind much earlier, avoiding the need for a last second 38 degree turn to even hit the South Tower.

Regarding the altitude over the lawn, have you factored in "ground effect?"
 
Hetware said: ↑
The final seconds of flight exhibited extraordinarily precise maneuvering.

No, "Hetware"....no it didn't.

Please watch this again:



That ( ^^^ ) is the full FDR recording, re-created from just before take-off at KIAD. Please F/F to time reference 1:10:00 if you don't want to be bored by the whole thing.

If you need interpretation of what is displayed, on the NTSB animation graphic, just ask. Myself, or TWCobra will be very capable to explain.
 
The fdr animation re-creation does have issues in that it did not account for mag dev and ends at the last full data frame rather than closer to impact.
However it does show very well the action on the yoke is not that of a precision flier.
 
Ground effect? With slats and flaps retracted, slight nose down, and at a velocity that would greatly increase the ratio of parasitic to induced drag.....
 
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The fdr animation re-creation does have issues in that it did not account for mag dev and ends at the last full data frame rather than closer to impact.

I believe the ending near the last data frame had to do with corruption AT impact, and a need to coax out the data more carefully as a result. There is an expert (cannot recall his name, atm) who did this. (ETA -- Warren Stutt, and Frank Legge: http://www.journalof911studies.com/volume/2010/Calibration of altimeter_92.pdf)

Magnetic deviation was another reference in your comment, and I'm slightly confused as to its relevance? Did you mean True versus Magnetic North, also known as "Variation" or more common in the modern era, "Declination"?
http://en.wikipedia.org/wiki/Magnetic_declination
 
Yes, the data that was available beyond the last full frames was decoded and is entirely consistent with the aircraft's so called official flight path and final disposition
 
Yes, declination, not deviation

<<hangs head>>

There actually IS a term called "magnetic deviation"....just not relevant here.

(ETA): It applies, in aviation, to localized influences on the magnetic compass, due to the aircraft structure itself. Semantics, mostly but still...something that ALL pilots learn about...in basic. This amounts to less than, equal to at most two degrees, and dates WAY back...hardly noticeable, today.

Might be applicable in instances of "test questions" involving dead reckoning problems...but, that's about it.
 
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There actually IS a term called "magnetic deviation"....just not relevant here.
I worked at a weather station in the 1980s that recorded variations in the magnetic field strength and direction. It was only a few hundred miles from the mag north pole

Mould Bay, NWT, Canada
Aka YMD
 
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But to the point, the only impressive part of the final manoeuvre was how impressively **** it was. I tried my best to recreate the turn on my AAL77 reconstruction but even I couldn't perform it that bad.

Edit: Yep Frank Legge and Warren Stutt
 
Oh and to characterize flt77 as coming in between the Navy Annex and the VDOT tower is rather specious. It was higher than the Annex so how well it managed to be laterally between the two is immaterial.
 
Oh and to characterize flt77 as coming in betwern the Navy Annex and the VDOT tower is rather specious. It was higher than the Annex so how well it managed to be laterally between the two is immaterial.

No need to explain....ANYONE who has physically walked this area (as I, and many others have) can easily visualize how the B757 was flown in.

On a personal aside, I did know a witness who lived on the fifth floor of an apartment building located on Columbia Pike....he saw the jet pass by his window. (Google Map image below, for reference. See the Pentagon on the right of the screen, Route 244 (Columbia Pike) was followed by the attacking hijacker pilot of AAL 77).

On this map, I lived (at the time) just near Lyon Park. Fillmore St. and Pershing Drive. (Slightly out of frame, at the top....where Washington Blvd (27) meets Route 50...and a bit more North, and West)

244.jpg
 
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