Jet engine sim for testing 9/11 planes

Originally posted by weedwhacker
Does anyone know if the CVR from AAL77 was recovered?

Yes it was recovered but no reports released on whatwas on the tape.

The Director of the FBI stated ther was nothing useful on the tape.



[edit on 25-5-2008 by ULTIMA1]

reply to post by ULTIMA1


ULTIMA, as to compressibility above 10000....the pitot-static systems, modern ones, are very well balanced because there is something called the ADC....the Air Data Computer. Actually, two of them, one for the CAPT, one for the FO....and there is reduncancy built in, between the various pitot tubes and static ports. The LEFT ADC receives the RIGHT Pitot, and left Static port, etc...and, of course, there is the STBY system, which can be electronically switched into the ADC...also, any ADC can be switched to either side of the cockpit...oh! The marvels of modern technology!!!

The ADCs receive also the SAT and RAT inputs....(So many acronyms....RAT in this case means 'Ram Air Temp'.....not....Ram Air Turbine.....entirely different system, but acronyms are acronyms.....)

We just say 'ram rise'....also, all of this info goes into the A/S indicator, to show current VMO (the barber pole) and current Mach number....of course, the Mach number window doesn't open, in the A/S indicator, until...somewhere above .34 to .36.....maybe .40......I forget, because Mach isn't important until WAY above 10000 feet.

added.....fighter jets, of course, are different....if they wish to exceed Mach at any altitude, their avionics are designed to display as needed.....

[edit on 5/26/0808 by weedwhacker]

Originally posted by weedwhacker
ULTIMA, as to compressibility above 10000....the pitot-static systems, modern ones, are very well balanced because there is something called the ADC....the Air Data Computer. Actually, two of them, one for the CAPT, one for the FO....and there is reduncancy built in, between the various pitot tubes and static ports. .

So then explain how compressiblity would effect the altimeters if they are so well balleneced as you have stated?

reply to post by ULTIMA1


ULTIMA.....do you bother to read my entire posts?!?!?!

Scroll up.....read.....read them again.....

[hint].....the ADCs were designed within certain expected parameters.....

In any event, you are deflecting the point (once again!!!!)

You have completely ignored anything I said about the altimeter setting question....NO, you just grab one sentence, and 'spin' it in some awful way.....really, this grows very tiresome.

I am trying, very hard not to get myself a 'warning' here, so I am staying calm, cool and collected....

ONCE MORE, for the record: ULTIMA continues to, if not break the T&Cs, at least flagrantly flaunt them.....I have never seen anyone get away with more one-line posts in my time here at ATS!!

Some one-line posts can be pure, on point, and acceptable....but that's not always the case with this gentleman. Instead, it becomes argumentative, with a focus on one aspect, usually out of context, in order to further distract and deflect the discussion. Am I the only person seeing this happen??

How much patience are we supposed to convey?

reply to post by ULTIMA1


ULTIMA, in response to your earlier post (please click the blue link above) regarding the CVR.

You said something about the FBI saying 'there was nothing useful'.....

Is this from a FOIA request you made?? Or, is this hearsay. Because, hearsay is not admissible in a Court of Law.

If the FBI said 'there was nothing useful' then, was that a snip from a fuller quote? Was the tape so damaged that it was unreadable?? WHAT is the full context of that FBI statement??

Either the FBI is hiding something (seems to be your allegation) or the tape was unusable (it happens)....I want to know the full extent of the FBI statement, not just a snippet. AND, you are the King of FOIA requests, how is it coming on the CVR from the FBI as pertains to AAL77??

Tell us, please sir.

Originally posted by weedwhacker
ONCE MORE, for the record: ULTIMA continues to, if not break the T&Cs, at least flagrantly flaunt them.....

Gee you really get bent out of shape when someone questions you.

Why do you have goet so upset, if i got upset everytime questioned me i would have gone postal by now.

Originally posted by weedwhacker

You said something about the FBI saying 'there was nothing useful'.....

If the FBI said 'there was nothing useful' then, was that a snip from a fuller quote? Was the tape so damaged that it was unreadable?? WHAT is the full context of that FBI statement??

Either the FBI is hiding something (seems to be your allegation) or the tape was unusable (it happens)....I want to know the full extent of the FBI statement, not just a snippet.

Tell us, please sir.

Also, where was it found, and how did it get there?



My theory is ATS doesn't care if he violates the T&C's because he generates traffic or attention.
Or perhaps because he's from the NSA and part of a mass disinfo campaign of which ATS is apart.

Originally posted by weedwhacker
You said something about the FBI saying 'there was nothing useful'.....

There are several sources for information on the flight 77 CVR.
This is just 1.

911research.wtc7.net...

“It’s extremely rare that we don’t get the recorders back. I can’t recall another domestic case in which we did not recover the recorders,” said Ted Lopatkiewicz, spokesman for the NTSB. And FBI spokesman Joseph Valiquette said “We don‘t know what was said in the cockpits, by the crew members or by the hijackers.” (Associated Press, 2-24-2002)

FBI Director Robert Mueller said Flight 77’s FDR provided altitude, speed, headings, and other information, but the cockpit voice recorder “contained nothing useful,” and he originally declined to say what was gleaned from both recorders on Flight 93 -- before Deena Burnett started her campaign described above. On September 15, 2001, Mueller told the Arizona Star that “the agency had gotten no information from the voice data recorder from Flight 77.”

Mueller said the [voice] recorder from the plane that rammed into the Pentagon was so badly damaged by fire that it would not yield any information. But the flight data recorder [from Flight 77] was recovered in usable condition as was the flight data recorder from the Pennsylvania crash. (Pittsburgh Post-Gazette, 9-21-2001)

However, in a Public Broadcasting Service (PBS) report on September 14, 2001, Dick Bridges, spokesman for Arlington County, Virginia authorities, told the Associated Press “the voice recorder was damaged on the outside and the flight data recorder was charred in fires that broke out following the crash.” This report directly contradicts statements made by FBI Director Robert Mueller; but no one has questioned the inconsistency.

Either the FBI is hiding something (seems to be your allegation) or the tape was unusable (it happens

How many times do you know of a CVR tape not being readable?

911research.wtc7.net...

A source close to the National Transportation Safety Board (NTSB) who asked to remain anonymous when asked about the " ongoing [black box] investigation, " told us that "the NTSB never closely examined the cockpit voice recorders (CVRs) and flight data recorders (FDRs) recovered from American Flight 77 which hit the Pentagon, and United flight 93 which crashed in Pennsylvania. " This, while the FBI has continued to quietly dodge vexing questions related to its prior knowledge of the 9/11 attacks and how the Bureau’s widely-reported inept and mishandled information protocol cost so many lives.

The source added that “the [CVR and FDR] tapes were sequestered by the FBI and quickly taken to its Quantico, Virginia labs where analysis was conducted solely under the Bureau’s influence in order to maintain complete control.” However, according to the individual with knowledge of the investigation, “there were a few NTSB officials allowed to observe, but their influence on the probe and tape inspection was minimal at best.”

We also talked to Michael Thompson, chief engineer in the CVR/FDR division of Allied Signal-Honeywell Corporation in Redmond, Washington -- according to his counsel, Mark Larson.

We asked Thompson if he was the person in charge of flight data recovery in the 9/11 investigation, since Honeywell manufactured the data recorders in operation on all four Boeing jets involved in the September 11 crashes. “I cannot answer that under advice from legal counsel,” he said.

Since his legal counsel, Mark Larson of Tempe, Arizona, was unavailable for a conference call, Thompson told us, “On advice of my legal counsel, I cannot answer any legal questions pertaining to that incident.” [On November 19, 2002 at 12:16 pm, Honeywell transferred our initial call to Mark Larson, corporate in-house counsel for Honeywell, who in turn told us to contact Michael Thompson regarding any questions we might have about the 9/11 CVRs and FDRs.]

[edit on 26-5-2008 by ULTIMA1]

reply to post by ULTIMA1


Thanks.....I'd like to read more of that, and in the meantime it should be an imperative to demand that the full force of investigation be conducted as to WHEN and HOW the FBI took (forced their) authority over the NTSB.

I would have loved to have been a fly on the wall in THAT discussion!!!

Would also be interesting to try a back-door approach....get at those Honeywell people....see IF the CVR was damaged beyond readability.

You know, of course....in decades past, the Flight Data Recorder was rudimentary.....a metal foil tape, moving very slowly, with needles inscribing the info....altitude, airspeed, heading....about twenty day's worth, maybe more. The advent of digital tech meant improvements!!

Hence, the DFDR. Everything encoded, digitally....no tapes, just binary code....hardened to survive many Gs at impact......

The old CVR....well, still about the same....a continuous loop, thirty minutes or so of tape......magnetic tape, just as you may remember from your 8-track cartridge you had in your car.....when we do a CVR test, in the cockpit pre-flight, we plug in a headset.....and make sure the CAM (cockpit area microphone) is working....there is a slight delay between your spoken voice, and what you hear....that is normal. Then, we push the green TEST button, and watch the meter flick four times, as it tests each track. That competes the test of the CVR. It is against FARs to pull the C/B on the CVR, except in the case of an accident or an incident.

However, it does have a nice red button to ERASE the tape....this only works when on the ground, with the Parking Brake set.

However, even after a bulk erase, modern tech can sometimes pull out snippets of old recordings, because of the vagaries of magnetic tape.

I provided all of the above to let non-pilots know what a CVR really is. It is a continuous loop, multi-track magnetic tape, similar to the the 8-track cartridges that us old timers may fondly remember....and often cursed at!!

This is encased in a protective box, designed to keep it safe in normal accidents, in order to re-construct something that would otherwise remain a mystery....in other words, most airline accidents.

A determined terrorist attack, with suicidal terrorists at the controls....not much mystery there. If there is going to be an allegation that the AAL77 CVR is under 'wraps'....then why did the UAL93 CVR be released??? Obviously, the tape survived intact enough to be understood (heard...since it's all audio).

AND, it tied in quite well with the DVDR, from UAL93.

Originally posted by weedwhacker
Thanks.....I'd like to read more of that, and in the meantime it should be an imperative to demand that the full force of investigation be conducted as to WHEN and HOW the FBI took (forced their) authority over the NTSB.

Well the FBI is the lead investigating agency, if the crash site is considered a crime scene, the NTSB provides tecnical support.

You should check out more of the flight 800 reports, about what went on between the FBI and NTSB.

reply to post by ULTIMA1


ULTIMA....are you referring to TWA800??

If so, then that deserves a different thread....could you direct me to one on ATS???

Originally posted by weedwhacker
ULTIMA....are you referring to TWA800??

Yes, what i stated was that you should check out the reports about what went on between the FBI and NTSB in that investigation also.

reply to post by ULTIMA1


ULTIMA.....really? Are you goiong to sully one investigation by trying to bring another into it???

Let's stick to one conspiracy at a time, shall we???

Start a TWA800 thread....unless one already exists....

BUT....don't deflect from THIS thread.....haven't I pointed this out often enough???

Originally posted by weedwhacker
Start a TWA800 thread....unless one already exists....

BUT....don't deflect from THIS thread.....haven't I pointed this out often enough???

Do you have a problem reading my posts?

My post was not about Flight 800 but about the power struggle between the FBI and NTSB, THAT YOU BROUGHT UP.

it should be an imperative to demand that the full force of investigation be conducted as to WHEN and HOW the FBI took (forced their) authority over the NTSB.

[edit on 27-5-2008 by ULTIMA1]

reply to post by ULTIMA1


Again.....ULTIMA wishes to not answer a question, but instead, make a new question....or take the topic in a new direction. Very typical....

AND, I have provided an olive branch, many times....get slapped away each time....

Let's try and focus on the topic and not on each other.

Thanx guys & girls.

reply to post by Gemwolf


Back to the 'jet engine Sim'

It is nonsense. It's a fun thing to play with, but it has no bearing what-so-ever with where this thread has veered to....

I believe I have posted enough, on this or other threads, to conclusively point out the fallacy of the OP's premise.....even if, with my, and other's help, we have gone a bit off the rails, at times....

We have gone many pages, and covered some ground....sorry, it's a uniquely American idiom....[covering ground]...

What we have learned is....the 'jet engine Sim' has no bearing on what actually happened on 11 Sept 2001.

I have pointed out, if not here, then on other threads, that a short term over-temp of a jet engine will not result in immediate destruction, and loss of thrust.

So, the point of this thread is moot.....the jet engine Sim is fun, but it has no relevance to the real events of 11 Sept, 2001

In relation to the AA77 FDR:

Re: Loral Fairchild Model F-2100 SSFDR

NTSB Number DCA01MA064
B-757-200, N644AA
American Airlines

This model SSFDR accepts serial bit stream data in an ARINC 573/717 format at a rate of 256 12-bit words per second. The SSFDR uses solid-state Flash Memory technology as the recording medium. The recording is stored in a Crash Survivable Storage Unit. A minimum of the last 25 hours of operational data is retained on the recording medium.

Prior to recording, the serial data stream is compressed using a modified Hoffman encoding scheme. The data can be decompressed and restored to the original 575/717 format without any data loss. This requires the use of specialized manufacturers or equivalent software.

The Digital Flight Data Acquisition Unit (DFDAU) provides a means of gathering, conditioning, and converting flight data parameters to digital data. In this aircraft, the DFDAU function is performed by the SSFDR. The DFDAU provides a serial binary digital data stream to the SSFDR at a rate of 3072 bits/sec. A binary, or logical one, is represented by a voltage transition between clock transitions.

The DFDAU input signals are time division multiplexed, with parameter identification established by means of position or time slot addresses in the serial data stream output. This output is a continuous sequence of four-second data frames. Each frame consists of four subframes of 256 separate 12-bit words, with the first word containing a unique 12-bit synchronisation (sync) word identifying it as subframe 1,2,3, or 4. The data stream is "in sync" when successive sync words appear at the proper 256-word intervals. If the data stream is interrupted, sync words will not appear at the proper interval or sequence, and the time reference will be lost until the subframe pattern can be reestablished.

What this means is that at least the final 4 second frame of data was unreadable due to loss of sync because it had not completed writing the frame when power was interrupted on impact. More than one 4 second frame could have been lost but just one would be enough as the plane was descending at 60-70 ft/sec during the final readable 4 second frame of data. Subframe sync was never re-established for obvious reasons - the plane was destroyed.

All that was readable after the final intact subframe is 2 timestamps 9:37:45 and 9:37:46. The rest was unreadable garbage and has been left off the decompressed copy.

In short, the data is NOT as questionable as some would like others to believe.

More recent DFDRs are capable of capturing valid data to within 1.5 secs of destruction but this was an earlier unit with worse limitations.

[edit on 27/5/2008 by Pilgrum]

reply to post by Pilgrum


Escellent find, Pilgrum!!

I keep using the John Wayne voice when I type your name....

I've been trying to tell the unknowing, in my incredibly inefficient way (using my own words) and you come along, and blow me out of the water!!

Very good work!!!

Originally posted by weedwhacker
AND, I have provided an olive branch, many times....get slapped away each time....

You really are a liar, do i have to show all the insultes you posted instead of olive branches.

How many times have you lied about me writing or selling a book?


[edit on 27-5-2008 by ULTIMA1]