We all know the Dept of Defense video shows an onject going level across the lawn. So "debunkers" have tried to offer the theory that the FDR altimeter may be lagging due to pressure differentials. I have plotted the last few seconds side by side to address this issue based on the FDR data.

Altitudes are in bold. Please remember the following altitudes are from the csv file and reflect Pressure altitude. You need to add 300 feet to get the actual altitude of the aircraft.

09:37:42 AM 307

09:37:43 AM 239

09:37:44 AM 173

09:37:45 AM
09:37:46 AM


Between :42-43: seconds is a 4080 fpm decent. A typical normal descent for a jet aircraft with a professional pilot at the helm.

Between :43-:44 seconds is a 3980 fpm descent. Again.. nothing major for a professional in a jet aircraft. This is even considered "normal". A steep descent sure.. but nothing "abnormal". Abnormal would be in excess of 7000 fpm.

The total fpm descent rate from 42-44 is 4020 fpm. Definitely a good rate of descent, but not abnormal for a professional pilot. Hani, if he did have training as a pilot in Cessnas, would only be used to 1,000 fpm descents. But we already know Hani couldnt control a 172, so i have no idea how he would handle 4000 fpm without hitting the pentagon lawn.

A quote someone was helpful to point out about altimeter lag...

e) Hysteresis: This error is a lag in the altitude indications caused by the elastic properties of the materials used in the aneroids. It occurs when an aircraft initiates a large, rapid altitude change or an abrupt level-off from a rapid climb or descent. It takes a period of time for the aneroids to catch up with the new pressure environment; hence, a lag in indications. This error has been significantly reduced in modern altimeters and is considered negligible at normal rates of descent for jet aircraft.
http://allstar.fiu.edu/aero/PSI.htm

Basically. The above quote is correct. That altimeters do lag. When you abruptly change altitudes. In other words, when you are level and quickly move the stick, you will see a lag in the altimeter momentarily. Then it catches up as your are in the descent. You will also notice most modern altimeters have reduced this lag and that it is negligible in modern jets (mainly due to static port design and computers installed on modern jets).

Another helpful quote from a training site I had found during a quick search (when arguing the lag issue). I used to actually teach this to new students when i instructed full time years ago in Cessna's and Cherokee's.

c. Lag in the altimeter.
(1) Make an abrupt pitch change and point out the momentary lag in the altimeter.
(2) Make small, smooth pitch changes and point out that the altimeter, for practical purposes, has no lag. .
http://www.geocities.com/cfidarren/iplesson1.htm

Now we see in the animation descent that it was deliberate, smooth and not abrupt. The descent rate wasnt abnormal for a modern jet. Therefore... no lag. This may be the reason why Boeing, the NTSB and the FBI do not want to help us decode the additional FDR data to help us confirm that there was most likely no lag. However, the data still needs to be decoded. You would think if this additional data supported the official story, they would be stepping forward to decode it. They arent. Also, if the additional data does lend itself to altimeter lag, then the increased descent rate would have to be explained as it currently conflicts with the DOD video of an object level across the pentagon lawn.



Now, if this altimeter is lagging, which we see from the above quotes it shouldnt be, the descent rate will increase from its present data and will be in further conflict with the Dept Of defense video (The "5 Frames Video") showing a level object crossing the pentagon lawn. The above object, which the NTSB says is AA77, its showing a 4000 fpm descent rate for the last two seconds of data in its present form. The video shows it level across the lawn for the very last second (1:26-1:27 in the above video).

If the official impact time was at 09:37:45, that means that AA77 would have had to pull out of a 4000 fpm descent instantaneously and be level across that lawn. IMPOSSIBLE! If this aircraft was too high to hit the light poles (480 feet as noted in the current data provided by the NTSB), it would have more time/altitude available to pull out of this descent and overshoot the pentagon. Leaving a fireball in its wake while quickly exiting the area. Very possible.

If you account for altimeter lag, the descent rate is increased to more than 4000 fpm.

Something is rotten in Denmark.

Now we all know why Boeing and the NTSB do not want to explain nor decode the further data we have. It will only conflict further with the DOD video if they want to use the "lag" excuse. But we know from the quotes its improbable the altimeter showed lag.

Final conclusion, either..

A. altimeter is accurate via the 4 sources of information we have that match and conflicts with the official govt story regarding the light poles and DOD video.

or...

B. The increased descent rate makes it that much more improbable (read: impossible) an object was able to be level across the lawn in the DOD video.

(I may add/edit for typos in the future on this post)

Also keep in mind, IVSI or Instantaneuos Vertical Speed Indicators (also in same articles quoted above) are on most modern aircraft/jets which virtually eliminate lag. The VSI is the most "laggy" instrument on any airplane. They add certain mechanisms inside the instrument to eliminate this lag problem associated with most primary aircraft with primary basic instruments.

Most beginner aircraft do not need highly sophisticated equipment to deal with lag as everything happens rather slowly in primary trainers.

As noted in the above post, modern equipment on jets eliminate lag.


Hope this clears up the lag issue for some of you. Feel free to ask questions. (Spin and trolls not welcome).

Also.. for those that know me... please tell these others you have looked up my name in the database and that you have seen my credentials.

I have already had to ban one troll who questioned my credentials based on a typo. (Piolets erent englush majurs...U shuld see sum of da piolets out there.)

So, Painter, Russell, Merc (and anyone else i trust please PM me and i'll send you the info), please tell these people you have seen my credentials so we can put an end to these weak strawman attacks. Thanks.


To the Strawmen out there.. .its only a matter of time before my name does go public. So if you want to continue with your "He aint a pilot" attacks.. its only going to make you look more like the fool you are when i am public. Keep it up.. ;)

I actually had one JREFer stalk me for 15 pages over at Colbertnation trying to get my name why ignoring and refusing to debate the facts. Colbertnation banned him. His JREF name is LashL. They need to put a leash on that guy...lol

Here are all of the 9/11 related documents now released by the NTSB.

http://www.ntsb.gov/info/foia_fri.htm

Thanks Russ.

Well.. it looks like the Radar Alt falls under "not working" or "unconfirmed".

[hmm]

http://www.ntsb.gov/info/AAL77_fdr.pdf

page 2.

Anyone want to take any guesses why they didnt want to "confirm" the Radar altimeter or put it in with the tabulated parameters?

JDX,

That was what I was noticing. Notice what is not on there too.

I should hear from my guy tomorrow. If you see anything else on these that is of interest to a remote guidance idea, let me know.

I have two questions on your altimeter stuff. If the plane was manufactured in 1991 would that be the right time frame for that equipment?

I was trying to read a little about that equipment (over my head) and in reference to approach avoidance there were a couple of comments about how it acts below 500 feet.

Any pertinence?

Russell

Going by file size of the .zip downloads.. none of them have the animation or .fdr file?

yup

There's a lot of charts and graphs I haven't seen though that you might be able to make sense of.

Not sure exactly about that specific aircraft.

However.. i know most of those aircraft are certified to what is called Category 2 and 3 ILS. Which means they are VERY accurate in terms of altitude. Again, this is in approach environment and usually relies heavily on the radar altimeter.

The fact that they wont release the Radar altimeter parameter speaks volumes.. especially when they will let conspiracy theories fuel on the data we currently have while refusing to address the issue or stonewalling it altogether.

Im supposed to hear back from my source hopefully mid-week.

Actually.. as far as i can tell... those file downlowds are from the JFK Jr. accident ...

Accident Synopses
NTSB Identification: NYC99MA178
July 16, 1999
Vineyard Haven, Massachusetts

And the Payne Stewart accident.. it appears...

Accident Synopses
NTSB Identification: DCA00MA005
October 25, 1999
Aberdeen, South Dakota

They only provide .pdf's for the Sept 11 analysis.

The file downloads are also not .zip files. I downloaded the first file #FOI99MA178 and its really an .exe. Yet it shows as a zip file as the icon. Im not opening it... lol

As for the graphs and charts. They are also on the GWU site i believe. I have seen them before. Its the same stuff we have, just graphed out.

It also speaks volumes they are releasing this data 5 years later.. meanwhile we are fully involved in war in the middle east based on 9/11. But that is a topic for another thread. Lets try not to get side tracked. I just wanted to get that in there....

Operation "Checkmate" is well underway. Keep your eyes peeled and your ears open. Major Airline unions have been contacted. Members of Congress have been contacted. The ball is rolling. Most likely down a snowy slippery slope.

UnderTow, please call me when you get a chance. I dont spend too much of my time on this forum anymore. Its time to start kicking down doors and getting answers. I'll give you an update.

For everyone else... try not to let the spin and ignorance of facts displayed here distract you.. .follow the facts that conflict with the official story. Ask questions. .demand answers...

Good luck johndoeX

Bumped for Russell to learn Vertical speed calculations.

Still havent head back from any of the above.

I have a favor to ask you.

Since you are presenting aerospace data that we are trusting and have questions about - could you please try to understand this is not our specialty?

None of us have time to learn and understand it all. This is why complimentary research is important. You can see I spend basically all of my time in between photography projects working on the aspects of the Pentagon that interest me.

I have a lot of questions that I don't have time to research. I know it may have been spelled out somewhere but there are times a concise answer helps or even gives a reference point to know where to begin looking for more details.

Just understand our learning curve - please.

Bumped for Parmeidies

My goal is not to prove that the OCT is correct. I'm not an idiot!

With regard to the Pentagon and the issue of FDR data, the eye witness accounts and physical evidence persuade me that a 757 did hit the building. I therefore believe any FDR data which deviates from that scenario by the amount under discussion should be examined carefully for possible sources of inaccuracy.

Do you have a precise citation for your authority on this? What was the most recent barometric reading from Reagan National at the time of the event?

That is not consistent with what I'm seeing. That rate of descent is significantly (5x to 10x) higher than the numbers I've seen while looking for safe final approach procedures.

A plot of the final 14 seconds from the FDR shows the plane was undergoing significant alternation in vertical acceleration. Without better information on how the reference coordinate system is established, I will not assume that "vertical" is identical with "vertical to the ground". Since we are dealing with a situation quite different from normal flight conditions, what is normally "negligible" may be significant under these conditions.

The quality of the video as well as the distortion of the camera lense makes that very difficult to assess. The average rate of descent in the penultimate second as indicated by the pressure data was 66 feet/second. It took about a second to fly from where the lamp posts were clipped to the face of the building. Since the lamp posts were on an overpass, it is not inconsistent to believe the plane descended another ~66 feet in the final second.

Reagan METARS
METAR KDCA 111251Z 35005KT 10SM CLR 21/14 A3021
SPECI KDCA 111341Z 33010KT 10SM CLR 23/14 A3022
METAR KDCA 111351Z 34009KT 10SM CLR 23/14 A3023
METAR KDCA 111451Z 32008KT 4SM HZ CLR 24/14 A3022
METAR KDCA 111551Z 33009G15KT 7SM CLR 26/14 A3021

The full analysis based on adjustment for True altitude using local pressure
http://pilotsfor911truth.org/pentagon.html

The rate of descent is based on the FDR. Do the calculations yourself. Take one time stamp, subtract the next, multiply by 60 (if you are unfamiliar with the formula). It is a VERTICAL speed. As in Vertical... vertical. If you are unfamiliar with the word "vertical". Merriam-Webster Online

Alternate analysis working back from the impact hole based on vertical speed.
http://z9.invisionfree.com/Pilots_For_Trut...c=84&st=0&#last

Depiction of the alternate analysis


Again.. alternate analysis is a hypothetical. For a more accurate analysis based on altimeter parameters corrected for local pressure which shows 480MSL, go here...
http://pilotsfor911truth.org/pentagon.html

Hope this helps...

Where is the key to explain the acronyms?

I'm talking about physics not semantics.

I have not seen enough information to establish the reliability of your analysis. The link to the NASA document makes me believe that under the conditions in question we cannot rely on the FDR to provide a resolution as precise as is required to determine exactly where the airplane was.