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Old 19th Sep 2011, 07:44   #41 (permalink)
 
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barit1, re your posts #26 and #39, and all those who have helped with this question,

You may be interested to see the path the plane would have flown, if it had passed north of the Citgo service station on the way to the Pentagon, as asserted by some websites. Calculation shows that the plane would be banked at 77 degrees to perform the turn at the known speed. Or it would if it could complete the roll from a left bank to a right bank in 0.5 seconds. If it needed longer than that, the bank would have been even steeper.





The second image above shows a plane at about 70 degrees. Funny than none of the many witnesses mentioned this sort of bank angle. All witnesses either said the bank was slight or did not mention bank at all. Apparenly the bank angle was not thought worthy of comment. Do you think we can safely conclude the plane actually flew pretty well straight from its last radar position to the impact point?

Last edited by gravity32; 19th Sep 2011 at 18:09.
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Old 19th Sep 2011, 13:39   #42 (permalink)
 
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Hi gravity32,

What does the FDR reveal with respect to aircraft attitude?

Or is that in your opinion bogus ?

ETA: Reduce the size of the image to prevent page over run.
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Old 19th Sep 2011, 16:55   #43 (permalink)
 
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skwinty,

I would like to show you a graph of roll and pitch for the last 30 seconds, during which full power was applied. There was a significant dive then a levelling off. Last pitch reading was -1.2 deg.

However I can't do it. I can copy the graph to the edit page but it disappears when I post.

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Old 19th Sep 2011, 16:58   #44 (permalink)
 
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What format is the graph?

PDF?

Place the file on Photo bucket and post a link.
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Old 19th Sep 2011, 17:02   #45 (permalink)
 
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Idem re the link to photobucket

CJ
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Old 19th Sep 2011, 17:17   #46 (permalink)
 
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The file is in Excel. I can copy it to Word and then to a pdf. However photobucket is only interested in images like jpg.

Why do the posting rules say I can't post attachments?

So I printed it, scanned it, sent to photobucket. There must be a better way. You can see there was a significant dive during this 30 seconds, and a pull up to almost level at the end, -1.2 deg. Re your question about the FDR file, I can find no reason to suspect that it has been tampered with. Everything seems to correlate. It is clear that the control is rather erratic, suggestive of inexperienced pilot.


Last edited by gravity32; 19th Sep 2011 at 18:07.
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Old 19th Sep 2011, 18:27   #47 (permalink)
 
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At first glance, it is clear that the roll was mostly positive and the pitch negative, heading towards level flight to impact the building.

Seems consistent with a large airliner flying at nearly 500 knots.
I am not an expert in this field so YMMV.
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Old 20th Sep 2011, 04:27   #48 (permalink)
 
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Yes the bank was positve, but erratic, as the plane did its circling descent, until about 20 seconds from impact, when the plane then flew straight to impact.

The bump in the pitch graph at 5 seconds suggests the pilot had caught sight of the VDOT antenna tower and eased the control column to ensure he cleared it, then pushed forward again, overdoing it and having to pull back to avoid hitting the ground before impact.

The maximum bank of 6 degrees, very brief, during the last few seconds, rules out any possible deviation round the service station, if the FDR data is to be believed, and I see no reason to doubt it.
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Old 20th Sep 2011, 07:36   #49 (permalink)
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Roll rate... ?...

400degrees/sec? not even close. that has an extra "0" in it... and is still wrong for the B767 or B757.

at high speeds, exceeding VMo, the wing "such as" on the B757 can result in roll reversal occurring, (have seen 2 separate sets of data on similar configurations where this has occurred).

A4 roll rate is noted fairly accurately, it will mess with the side of your helmet.

For jet transports at high speed, the flightpath vector is not going to change substantially without pulling extreme g loads, and that will pretty much mess up the wreckage location.
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Old 21st Sep 2011, 04:10   #50 (permalink)
 
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For those who wish to learn more regarding this topic and "gravity32".....

Read here...

Frank Legge Begging For Peer Reviewers For Pentagon Paper - Pilots For 9/11 Truth Forum

and here....

Frank Legge Begging For Peer Reviewers For Pentagon Paper - Pilots For 9/11 Truth Forum


And understand that "gravity32" hasn't a clue with anything related to aeronautical knowledge.
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Old 21st Sep 2011, 04:13   #51 (permalink)
 
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Quote:
at high speeds, exceeding VMo, the wing "such as" on the B757 can result in roll reversal occurring,
Exactly.

It is also covered here....

Full Film - 9/11: World Trade Center Attack - Pilots For 9/11 Truth Forum

Unfortunately, a chemist named Frank Legge is trying as hard as he can to discredit seasoned pilots. Unfortunately for Frank Legge, he will not be able to distort aerodynamics or the truth.

CJ, do you still think that a radalt can accurately measure Absolute Altitude at anything less that 330 fps descent rate?
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Old 22nd Sep 2011, 07:53   #52 (permalink)
 
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Roll rate again

This thread started with a discussion of roll rate for a 757. Various opinions were expressed. Eventually it became clear that roll rate was not the right question for the case at hand. Roll rate describes a continuous process. What we needed to know was the initial behaviour of the plane when a full control input was applied, taking into account the inertia of the heavy plane. It seemed this would be hard to discover.

The calculation at the beginning of this page showed that a bank of 77 degrees would be required if the plane passed north of the Citgo service station. That calculation was based on an assumption that the roll from left to right could be completed in 0.5 seconds.

The required information is apparently now available from the FDR of UA 93. We see that full application of the control wheel produces only about 30 degrees of roll in the first second.

Can we can conclude from this that the calculation shown at the beginning of this page, that a bank of 77 degrees would be required, with a wing loading between 4 and 5 g, is a gross underestimation? Is so, the plane simply could not have performed the maneuvre required to pass north of the Citgo service station and still arrive in the vicinity of the impact point.
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Old 22nd Sep 2011, 14:19   #53 (permalink)
 
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9/11: The North Flight Path (official Release), Aerodynamically Possible - Witness Compatible



The North Approach, Technical Supplement to "9/11: The North Flight Path"

"gravity32", you may also want to look up the definition of Maneuvering speed with respect to the full and abrupt control wheel movement as seen in the UA93 video you posted above.
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Old 22nd Sep 2011, 15:44   #54 (permalink)
 
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A320,
Of course, if you slow the plane down and ignore the direction the plane was flying prior to the alleged deviation round the Citgo service station, you can get it to perform a viable curve. However even then the 300 knot curve has a bank of 45 degrees. No witness mentioned a bank anywhere near that large. And those witnesses that did mention a bank indicated the bank did not commence until the last second or two, greatly reducing its effect.

Here is an image showing the prior flight path as established by four independent radar facilities.



The track they show is heading straight for the Pentagon impact point. The last radar position is not far from the Sheraton Hotel. If you start your deviation there you need a left turn then a right turn. None of the diagrams in the above video show the left turn. Many witnesses spoke of the engines "spooling up" and "full throttle" so it is hard to see how the plane could have slowed down. The FDR file shows the plane accelerated and flew straight in this section. The radar positions confirm the speed shown in the FDR file.

Certainly you can draw a curve around the service station but do you not agree that you have to ignore a lot of evidence to do so?
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Old 22nd Sep 2011, 16:09   #55 (permalink)
 
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Quote:
However even then the 300 knot curve has a bank of 45 degrees.
You need to check it again.




These are the various paths based on returns from local radar.



FlickCabin.com - AA77TNi1_img_extZoomOut.jpg

You have cherry picked data to suit your bias. When you average the above flight paths based on radar, it lends itself to a northern approach, which is incompatible with the physical damage.

Also, it appears you trust data provided by government agencies and turn a blind eye and ear to witnesses cherry picking those to suit your bias while also misrepresenting what those witnesses have said, at the same time you distrust the data provided by the NIST and you feel the WTC was destroyed by controlled demolition based on witnesses describing explosions and what some have described as paint chips which you feel are some super military grade nano-thermate.
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Old 24th Sep 2011, 02:28   #56 (permalink)
 
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A320Slave, would you mind reducing the size of your image to avoid upsetting the text?

Regarding the course of the plane, let us see how it looks if we take into account the best evidence we have about bank angle. Hemphill says the plane was always on his right and went straight to impact with the Pentagon. See his line of sight in the image below. Morin says he stepped out from between the wings of the Navy Annex and watched the plane descending, going parallel with the Annex, and therefore straight. Darrell Stafford and Darius Prather show the plane was wings level going over the roof of the Annex. See their illustrations below.

Stafford: "Flat on top of the roof" [of the Navy Annex]


Prather: "This is the Navy Annex.." [His left hand]

Clearly we cannot start the turn until the plane has cleared the Navy Annex. You say we should not trust the radar track, so let us move the track northward to ease the turn as much as possible. The plane was viewed through the southern windows of the Sheraton Hotel and Paik's workshop, so we cannot place the track further north than their positions. The long thin yellow line is the track as determined by radar. The green line is the track shifted north. The turn, shown in red, commences at the edge of the annex. Half a second is allowed for rolling from a left to a right bank, which is impossibly short, thus easing the turn further.



What do we find? The radius of turn is 1599 feet. The average air speed according to the FDR for the last four seconds was 480 knots. This gives a bank angle of 85.5 degrees with a wing load of 12.8g.

Clearly that won't work for you. We will have to ignore a bit more evidence. We will ignore the speed and acceleration of the plane as determined by radar:



Witnesses say the plane was "spooling up", "full throttle", "powered descent" and " the noise was absolutely deafening". That seems to indicate the plane was speeding up, as shown by radar and in the FDR file, where we see the throttles pushed fully forward for the last 30 seconds. But let us ignore all that and see how slow the plane would have to go to achieve a bank of say 30 degrees. We find it is 102 knots.

But it is worse than that. Prather makes it clear the plane travelled some distance past the Annex and descended before the turn commenced.


Prather: "It dropped down a little bit."


Prather: "and then it started angling."

If we take the delayed turn into account, the g-force and bank, already impossible, will become astronomical. I think you would have preferred the previous more conservative analysis where we assumed the plane started to deviate at the last radar position. That gave a bank of 77 degrees and a load of 4.8g.

It is clear Stafford and Prather misjudged the position of the plane and thought it was closer than it was. They were not really in a good position to judge the distance, being near the cemetery, but the angle of bank near the Annex would have been very clear and easy to get right. Hemphill was the one who was in the best position to see the alignment of the track and he asserted that it was always on his right and that "it didn't turn left, it didn't turn right". He also mentioned ground effect, indicating he perceived the plane as very low and wings level. He made no mention of bank at all. Surely a bank of 77 degrees, as in the first calculation above, would have been very clear to him but he made no mention of bank.

Many witnesses described the approach of the plane to the Pentagon. None mentioned a steep bank. Few mentioned the bank at all and those that did said it was slight.

Is there any conclusion possible other than that the plane flew pretty well straight from somewhere near the Annex to the impact point?

Last edited by gravity32; 24th Sep 2011 at 03:12.
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Old 24th Sep 2011, 04:26   #57 (permalink)
 
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These are the tracks as drawn by the witnesses.



These are the witnesses themselves.



Here are more witnesses which have stated they "bet their life" on the flight path, which includes two pentagon police officers that you have said are either lying or mistaken.



More witnesses drew their flight paths as depicted here in orange.



Here is another flight path animation which corresponds to the witness flight paths depicted above.



All of the above are corroborated.

"gravity32", your flight path is cherry picked to suit your bias and is intellectually dishonest when taking into account all the information.. A bias which has an astonishing double standard considering you feel the WTC was destroyed by controlled demolition using some type of classified super duper military grade "nano-thermate".

The video I posted in post 53 is the type of analysis which is intellectually honest when taking into account all of the information. Many paths are aerodynamically possible and witness compatible. I suppose we will have to agree to disagree once again. Let us know when you will get one pilot to sign their name to your papers. So far, it appears you are 0 for 3. 0 for 11 if we count your revisions.

Last edited by A320Slave; 24th Sep 2011 at 04:52.
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Old 24th Sep 2011, 05:38   #58 (permalink)
 
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A320Slave,

For the plane to pass near the Navy Annex with wings level it would have to get into a steep bank to deviate round the Citgo service station. Do you honestly think Stafford and Prather looked at the plane banking at about 80 degrees and didn't notice it was banking?
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Old 24th Sep 2011, 05:55   #59 (permalink)
 
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Forgot to add this.

For those interested in listening to the interviews filmed on location of the above witnesses, here is the video.

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Old 24th Sep 2011, 06:45   #60 (permalink)
 
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For those interested in what really constitutes corroboration and cherry picking, here is a list:

Over a hundred people are on record as saying they saw the plane hit the Pentagon.
About 13 people said they thought the plane flew north of the Citgo service station.
Of the 13 who said it flew north of Citgo, all those who were in a position to see the Pentagon said it hit the Pentagon.
Hundreds of people were in traffic jams around the Pentagon and would have seen a plane fly over but nobody has said they saw a plane fly over.

A320 and friends insist that because 13 corroborate one another it must be true. What about the 100 plus who corroborate impact?

So much for corroboration.

If you look at the full videos of the people interviewed who support the north path you will find some interesting things. For instance Sgt LaGasse demonstrates with his hands that the plane went in at an angle and says "When the plane hit it just kinda disappeared." He indicated that his memory for details might be flawed but his memory of impact was not. "There is only one thing that is irrefutable .... the fact is American Airlines plane went from here into the building. You can pick apart everything else."

And Turcios. He said the plane was to the north but when asked if he saw the plane fly over he looked surprised and said "Fly over? No the only thing I saw was .... on a direct line to the Pentagon. It collided."

And Chad Brooks said he watched the plane "awfully low .. just go nose dive into the Pentagon ... full throttle .. clip the lamp pole ... just the sheer impact ... it just literaly disintegrated the plane."

So they didn't just cherry pick the witnesses who were prepared to say the plane passed north of Citgo, and avoid interviewing all those who saw the impact, they also cherry picked the parts of the interview that suited their story.

So much for cherry picking.
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