9-11: Impact Times; Infra-red Data Released by NSA

Addendum October 9, 2014

This addendum makes one correction and adds a PDF of my May 15, 2014 appeal letter. Based on the date of that letter it took NSA not quite five months to reconsider. Here is a link to my appeal.

IR Appeal Letter May 2014

Data Release

On October 4, 2014, I received a letter from the National Security Agency, Central Security Service, dated September 23, 2014.  The letter responded to Mandatory Declassification Review (MDR) case 70401 (NARA case number NW 168), my appeal to an earlier complete denial of all infra-red related information.

The release authority has now provided graphic analysis of the data for all four impacts, as originally provided to the Commission. The times, in all cases, are consistent with the times established from radar files and air traffic control tapes.

Here is the transmittal letter for the information release.

NSA MDR Letter Sep 23 2014

I addressed the total denial of all infra-red related information in a short post on March 25, 2014 under “Current News.” It took just over six not quite five months for the National Security Agency to reconsider. I based my appeal narrowly, asking only for the infra-red impact times, and nothing else. That is perhaps a lesson learned  for researchers and historians, present and future.


The 9/11 Commission Staff requested infra-red data concerning the impacts of the four hijacked airplanes on September 11, 2001.  The staff took that extra step because an analysis of seismic data by a separate individual reported a impact time for United Airlines Flight 93 three minutes after the 10:03 EDT impact time as determined from radar files and air traffic control tapes.

It is important to know that the later time, 10:06 EDT, was not a seismic data time. It was the extrapolation and interpretation of seismic data by a single individual. His coauthor and the sponsor of his article, the Maryland Department of Natural Resources, chose not to validate and verify his work when asked to do so by the Commission Staff. Instead, they simply referred the Staff back to the person who had made the extrapolation. I addressed the seismic issue in detail in an article published in 2010.

In 2011 during a visit to the National Earthquake Center, Golden, Colorado, I informally asked the staff there to take a look at the interpretation that led to a time of 10:06 EDT. They, too, declined, and simply referred me back to the original author.

The Staff Request

The original request is “Document Request No. 4-34: Final data from the Defense Special Missile and Astronautics Center (DEFSMAC) that established the time of impact for each of the hijacked aircraft.” The response to the Commission was classified “SECRET//X1” and was titled (U//FOUO) NSA’S ANSWERS TO DoD DOCUMENT REQUEST No. 4-34.” The response is annotated NW#: 168 DocId: 8977.

The Response

There are two graphs that are accurate to the minute and the approximate seconds for each impact, if extrapolated. The following chart depicts my current extrapolations. The intensity measurement is in Kilowatts per microsteradian (KW/sr-μ).


Impact Time


AA11 8:46:30+/- 250 KW/sr-μ
UA 175 9:03:10+/- 3500 KW/sr-μ
AA 77 9:37:30+/- 900 KW/sr-μ
UA 93 10:03:10+ 2000 KW/sr-μ

One graph depicts the times for all planes except UA 93. A second graph pertains to UA 93 and incudes a peak intensity time centered on 10:03:16-17+, and a dissipation time of 10:03:25+  Peak intensity was recorded as 5000 KW/sr-μ.  That graph provides an approximate measure of the time the fireball was observable, a period of about 15 seconds.

There is no data to indicate that DEFSMAC considered peak intensity for the other three impacts.

I do not recall making an extrapolation while on the Commission Staff. It was clear from the graphs provided that the infra-red times were consistent with other primary source data.  In particular, the infra-red data was conclusive for a 10:03 EDT impact time for UA 93, not 10:06 EDT, as had been speculated.

Here is the graph titled: “Aircraft Impacts – NY & DC, 11 September 2001 – IR Intensity vs Time (Zulu)

IR impact times AA11 UA175 AA77

Here is the graph titled: “Impact of United Flight 93 – Pennsylvania, 11 September 2001 IR Intensity vs Time (Zulu)”

IR Data UA93


This completes my work on all speculation that the seismic extrapolated time is relevant to the impact on UA 93. It is not, now, and never was. All such speculation is based on the work of a single individual who informed the Commission Staff that the seismic data, itself, was not conclusive.

At some future time a scientist or engineer will examine the original raw data—seismic, radar, and infra-red—and will find that the three data sets are consistent.

9-11: UA93; The Gofer 06 story, explained

Addendum added Feb 27, 2014

Here are links that provide additional insight into my work on the UA 93 story.

Seismic data considered

A 2009 article with a graphic showing tracks


A correspondent recently contacted me to discuss the relationship of United Airlines flight 93 (UA 93) and Gofer 06, the Minnesota Air National Guard C130H.  The correspondent speculated that there was an important relationship which was crucial to an incident time of 10:06 for UA 93.  The 10:06 time was an extrapolation from seismic data by a single individual who, when queried by the 9-11 Commission Staff, agreed that the seismic data was not conclusive concerning UA 93.

Nevertheless, the correspondent concocted this explanation:

I need to review the testimony of C-130 pilot Captain Steve O’Brien before the 9/11 Commission. What he had to say is highly relevant. Why? Simple. That morning, O’Brien had a bird’s eye view of the Shanksville crash site – and was in position at the right moment to be a witness to whatever happened at 10:06 AM, which is the crash time indicated by the seismic signal.

At that very moment, he was in the cockpit of his C-130 looking straight at the crash site from 24,000 feet, after being prompted by the Cleveland ATCs.

Are you aware of what O’Brien told the commission? Do you know if his testimony has been released? I have searched for it without success. Did the commission ask him what he saw at Shanksville?

The issue looks to be of primary interest, because it does appear that someone tampered with the 20-page transcript of the real time conversation that O’Brien had with ZOB Cleveland ATCs, on the morning of 9/11.

I believe that transcript offers some powerful clues about what transpired. I am attaching the file below. It’s pretty big — apologies for the size. Or you can download it at [http://www.911datasets.org/]

The file includes a number of transcripts. The relevant ATC transcript has 20 pages. The key page is 18 of 20. You will notice that at 1405:45 O’Brien mentions that he sees smoke at the site. But, notice, he says the smoke is at 3,000-5,000 feet. There is no indication it rose from the ground, i.e., from a crash. This is an extremely important detail, as we shall see.

Then, after 1406:27, something strange happens. Four minutes of the transcript, from 1407-1411, appears to have been deleted. It’s gone!

Why do you think?

Could it be because O’Brien saw the unspeakable, i.e., saw a cruise missile crash at 10:06 AM — and reported this to the ATCs? This observation, had it been reported to the commission and/or made public, would have exposed the entire official 9/11 story as a HUGE lie, and at the same time would have revealed a criminal conspiracy in the act of “cleaning up” flight UAL 93, which had turned into a fiasco.

I now suspect that the Shanksville witness [redacted] saw a cruise missile just before it crashed — not a UAV. She told me it was “tubular” and “cylindrical” and had fins — but no wings. This sounds like a missile.

But why a cruise missile? Well, if the perpetrators decided to terminate UAL 93 by detonating explosives which had been pre-planted on the aircraft — they still needed a crater in the ground to serve as the basis for a cover story that UAL 93 had crashed, when in fact it was exploded at 3-5,00 feet.

Any help you can provide in locating O’Brien’s testimony before the commission would be greatly appreciated.

Sincerely for 9/11 truth,


I interviewed Lt Col O’Brien by telephone. The interview has not been released, according to the National Archives. My contact there reports that they have found a pointer to the interview and they will have it reviewed for release. I do not recall if the report of interview was an MFR or a recording.

O’Brien was asked the key questions.  Did he at any time at all see a military aircraft and/or any evidence of a missile?  Was he armed, had his C130H ever been armed, had any C130H model ever been armed? O’Brien responded in the negative to that round of questions.

I have again reviewed the transcript, the radar, and the audio files.  The correspondent distorted the story.  O’Brien never had a birds eye view. He was never prompted by air traffic control.  He initiated the report of smoke.  He was briefly considered as a candidate aircraft to circle the crash site but was not so tasked. A civilian aircraft was vectored to circle the crash site and provide GPS coordinates.

This is an old story, recycled.  Now is a good time to set the record straight.

Air Traffic Control Communications

The tape of interest is file 148-911-03003840k.s1, the Cleveland Air Traffic Control Center tape of Imperial Sector for the period 1340-1418 UCT (0940-1018 EDT).

Gofer 06 checked in, routinely, shortly before 10:03 EDT reporting an altitude of “two four zero” (24,000 feet.) Here is that exchange.

1002 Gofer 06 Checks in

A minute later, air traffic control turned Gofer 06 to a heading of 030 (North North East) away from the projected path of UA 93. Concurrently, Cleveland Center was losing UA 93 on radar, telling Gofer 06 that he was heading east, but now turned to the south.

The radar clearly shows the turn to the south to be the plunge to earth. UA 93 impacted during this conversation with Gofer 06.

1003 Gofer 06 Turned to 030

Over a minute later, Gofer 06 was told he would be run north about 26 miles before a return to original heading.  Gofer 06 then volunteered a report of black smoke at his “9 o’clock” (easterly).  The pilot could not tell if the smoke originated from the ground or from the air. Air traffic control was satisfied with the report and cleared him “direct Dryer,” about 10:06. The radar shows that Gofer 06 did return to original heading at that time.

1005 Gofer 06 reports black smoke

None of O’Brien’s report or subsequent conversation with air traffic control correlates to a speculated crash time of 10:06.  It is clear from this primary source information that UA 93 was down well before that time.  O’Brien was not queried further by air traffic control about anything that might have happened in the 10:06 time frame.

The Next Five Minutes

The Correspondent claimed, “Four minutes of the transcript, from 1407-1411, appears to have been deleted. It’s gone!”  That is a misinterpretation of the transcript. Here is what the certified transcript (ZOB-ARTCC-287 N591UA(UAL 93) for Imperial Sector actually contains:

1406:27 GOF06 ok direct dryer gopher zero six
1411.11 UNKN (unintelligible)

Here is the actual audio for that nearly five-minute period during which there were no transmissions. All the transcriber was doing was noting, for the transcipt record, the minutes that were passing with nothing to transcribe.

1007 Five Minutes no transmission

Crash Site Confirmation, Gofer 06 Considered, Not Tasked

Once Gofer 06 returned to original heading its path took it a few miles north of the crash site. The controller advised another controller that he could vector Gofer 06 to verify the crash site. This next conversation, an internal one at Cleveland Center, confirms that Cleveland had used a different plane and that the “lat long” of the crash site had been verified.

1011 Positive ID Gofer 06 not tasked

Grounding all flights

The order by the FAA’s Air Traffic Control System Command Center to ground all airplanes played out differently at different locations.  The emphasis was on grounding commercial traffic.  There was initial confusion as to whether or not the order pertained to military and emergency response aircraft. Here is how that order played out in the airspace controlled by Cleveland Center that included Gofer 06.

 1015 Only One in Air is a Military Plane

After that internal Cleveland Center conversation, the controller thought that he should ask Gofer 06 why he was still in the air.  Gofer 06 responded, no one told me to land. Gofer 06 then asked if anyone else was in the air. The last thing heard on the tape is the Cleveland controller telling Gofer 06 that “he would expand,” meaning he would zoom out so his scope would display a larger area.

 1017 No One Told Me to Land

Grounding of All Traffic, A Comment

One air traffic control facility posed a direct question about the status of military and emergency response flights.  I believe the question came from National TRACON and that the answer was that such flights would be allowed. I will update with that audio clip when I find it.

At no time was Gofer 06 told to land, nor were other military aircraft in the air. The only specific restriction to all flights, regardless of status, was a warning not to enter Class B airspace in the DC area. Those warnings started after 10:05 EDT.

Chaos Theory: UA 93; disruptive feedback, an interesting analysis


The purpose of this short article is to document for the record an analysis of the final chapter in the UA 93 story.  In the language of chaos theory, UA 93 became disruptive feedback once Cleveland Center entered a new flight plan for the hijacked plane in the air traffic control system, with destination Reagan National Airport.  The disruptive feedback that United 93 was still in the air confounded the national level at the time and in the accounting in the aftermath.

UA 93 lost on TSD at 1028 EDT

Here is a clip from the F2 Position, National TRACON (1 DCA 101-102 Tape 1-2 F2 1327-1450 UTC, as archived by NARA as part of the Commission files)  The F2 Position controlled the Andrews fighters once airborne.  As of 1028 the F2 Position knew that there was no target associated with UA 93. 1028 UA 93 not in system

In previous articles I have dealt with disruptive feedback, primarily in terms of the false report of AA 11 still airborne and the erroneous report that Delta 1989 had been hijacked.  In the language of chaos theory feedback is disruptive if it results in “a gain” to a system.  Concerning events of 9-11 that “gain” was the addition of planes the either had ceased to exist or were not in distress.  By that measure, the introduction of a new flight plan for UA 93 by Cleveland Center became disruptive.  That action by Cleveland Center was beneficial to air traffic control, specifically Cleveland and Washington Centers.  It was not beneficial to the system at large as we shall see.

Here is a link to analysis done by Brian Stark (Boone870 on the web) some months ago.  That analysis included the audio clip from National TRACON.  Stark’s analysis remains the definitive work on the UA 93 Traffic Situation Display (TSD) story, as told in the primary source and secondary information material of the day, supplemented by later recall by Transportation Secretary, Norman Mineta. 

(Note: the link in the last slide is no longer active)

Even though UA 93 was reported down with an impact time of 1003 EDT the flight plan was displayed and updated in the Traffic Situation Display (TSD) system until the flight “landed” at 1028 EDT at Reagan National.  It was that “landing” that was concurrently reported to National TRACON by an FAA caller who was watching a TSD display. (In context, the FAA caller was likely either Baltimore or Dulles TRACON)

It was the “approach” to that landing that became the threat to the National Capital Region, as updated to Secretary Mineta by Monte Belger, according to Mineta’s interview the next year with MSNBC.

It would be nearly ten more minutes before the first Andrews fighter took off in pursuit of an airplane that no longer existed, in fact or in projected flight plan.

9-11: UA93; FDR and CVR links

The purpose of this short article is to provide links to the CVR and FDR files for flight UA 93.

Flight Data Recorder (FDR)

Here is a link to the FDR readout as provided to the Commission, archived by NARA, and posted by History Commons on Scribd.  The readout shows that UA93 started erratic maneuvers shortly after 9:58 and started climbing at 9:59, ultimately to 10,000 feet altitude by 10:02.  The speed readout showed up and down variations beginning about 10:01.

At 10:02 the aircraft began its plunge to ground, accelerating from 300 knots to 500 knots at impact.  NTSB determined the impact time to be 10:03:11.  The Commission used NSTB-computed impact times for all four hijacked aircraft.

Cockpit Voice Recorder (CVR)

Here is a link to a time-stamped transcript in English and Arabic as provided to the Commission Staff by the FBI, archived by NARA, and posted by History Commons on Scribd.

The CVR correlates to the FDR in every respect.  The words “Yes, put it in and pull it down” were spoken shortly after 10:01, followed by the words “down, down” at 10:02:18, and “pull it down” at 10:02:23.  The recording ended at 10:03:10.9.

Transponder back on

During the plunge to ground the transponder became activated.  That fact was noticed by Cleveland ATC and reported in near real time to Herndon Center.  At 14:02:45 a reinforced (radar and beacon) return (84th RADES data point, corrected) showed the plane to be at 7800 feet.  At 14:02:57 a beacon (transponder) only return (84th RADES data point, corrected) showed the plane to be at 6100 feet, an instantaneous descent rate of 8500 feet per minute, a rate that was increasing as the plane accelerated.

Convergence of evidence

The primary source evidence is conclusive as to the fate of UA 93.  The hijackers flew it into the ground while under attack by the passengers and remaining crew.  It impacted at 10:03:11.

Any other explanation is speculative and without merit.

9-11: UA93; impact time, seismic data considered


I recently obtained some of the seismic data concerning UA 93 and that provides an opportunity to discuss an old issue about 9-11, the impact time..

Readers may recall that there was at one time some speculation that a study based on the seismic data suggested that UA 93 impacted at 10:06, three minutes later than all available primary source information indicated.  The Commission Staff treated that speculation seriously and ran the issue to ground. 

This article is the story of the data and of how the Staff dealt with one of the 9-11 family questions.

Data Source

The Incorporated Research Institution for Seismology (IRIS) has protocols for assisting educators, researchers, students, committees, and the public.  The link provided is to the protocol for researchers.  I found the IRIS staff helpful in obtaining the information available.

To run the data I used GEE, Global Earthquake Explorer, and an IRIS-provided link to AmaSeis. (Amateur Seismometer).  Readers with seismology experience will find additional programs available from IRIS at the same link.

My point of contact provided me the files I actually used.  He obtained them by submitting a Seismic Query to determine what data were available.  He then submitted a request via email using BREQ-FAST.  Finally, he converted the files to .SAC format via rdseed.

The Data

An undated report, “Seismic Observations during September 11, 2001, Terrorist Attack,” concluded: “we infer that the Flight 93 crashed around  14:06:05 +/- 5 (UTC).”  The primary author, Won-Young Kim considered data from four seismographic stations.  From closest to Shanksville to the furtherest, the sites were: Mont Chateau, (MCWV); Standing Stone, (SSPA); Soldier’s Delight, (SDMD); and Millersville, (MVL)PA.

In his vertical component assessment, Kim initially considered all four seismic stations.  He assessed that the signal to noise ratio was too small for both the closest site (MCWV) and SDMD, on the order of 1:1.  Therefore, he reduced his analysis to the Standing Stone station where the ratio was 2.5:1.  He also established that the ratio at the most distance site, Millersville, was about 2:1.

Kim based his analysis on the Standing Stone station only, ignoring the fact that the data from the closest station was inconclusive.  Further he extrapolated only two minutes of data beginning with an estimated origin time of “14:06:05 (10:06:05)”  We have no evidence that Kim examined earlier times, specifically 10:03.

IRIS has available only the data from Mont Chateau and Standing Stone, the two stations closest to Shanksville. My contact provided 10 minutes of data, from 10:00 to 10:10.

I examined the data as far as my expertise would take me (undergraduate geophysics classes) and found nothing anomalous to support a time of 10:06 rather than 10:03.  I leave it to practicing seismologists that might be interested to provide a more definitive assessment.

Let’s now return to the issue raised to the Commission.

The Question Posed

A 9-11 Family Member told  me via e-mail that seismologists agreed that UA 93 crashed at 10:06, not 10:03 as NORAD said.  I took that request for action and we obtained a copy of the report.  It was not a U.S. Army document; the Army referred us to the Maryland Geological Survey website for a copy.

We found that the time in the study, 10:06, was at odds with all other primary source information, the convergence of which supported a crash time of 10:03.  Despite that convergence we took the time to fully consider an alternative time of 10:06, as requested.

Primary source information

Data from the UA 93 Cockpit Voice Recorder (CVR) and Flight Data Recorder (FDR), air traffic control communications, FAA radar, and Air Force radar established a crash time of 10:03.

The seismic data was also primary source information; the study that inferred at time of 10:06 was not.  Statements that the seismic data show that UA 93 crashed at 10:06 are inaccurate.  Further, statements that leading seismologists and scientists concluded that UA 93 impacted at 10:06 are disingenuous.  The work was that of a single person, as it turned out.  Here is how we proceeded.

Steps taken

The study was sponsored by the Department of Natural Resources, State of Maryland under contract number SMGS/AG1-01-075.  The authors were Won-Young Kim, Lamont-Doherty Earth Observatory of Columbia University, and Gerald R. Baum, Environmental Geology and Mineral Resources Program, Maryland Geological Survey.

Our first step was a request to the Maryland Geological Survey (MGS) asking them to validate and verify the study done by one of its employees. The MGS declined stating that the work was primarily that of Won-Young Kim and that we should address our request to him.  The MGS, literally, walked away from the issue.

The second step, then, was to contact Mr. Kim, which I personally did.  Over time, I exchanged a series of emails and phone calls with Mr. Kim.  I informed him that multiple other primary sources of information did not support his work.  His position was that, if so, he still had confidence in his work.  Ultimately Mr. Kim agreed to a statement that the seismic data was not conclusive concerning the crash of UA 93.

Given that statement, we reconfirmed that the preponderance of evidence supported a time of 10:03 and that became our position.  There was, however, another avenue we could explore.

Going the extra step

Even though we had a high degree of confidence in the 10:03 time, we decided to treat the two times as equal and sought and obtained additional primary source information, infra-red satellite data.  We asked the Defense Special Missile and Astronautics Center (DEFSMAC) for the times it had established for the impacts of all four hijacked planes.

We had noticed in the Cheyenne Mountain Operations Center (CMOC) logs that some “IR [infrared] event” times had been entered that morning and assumed that DEFSMAC had recorded all four “IR events.”  They had, and the data provided was consistent not only with the 10:03 time for UA 93 but for the other three impact times, as well.  The DEFSMAC response is in the classified Commission files held by NARA.

To put it another way, we gave the two disparate times–10:03 and 10:06– equal weight and went to a tie breaker, even though there was no compelling analytical reason to do so.

A comment on DEFSMAC

Accurately reporting “IR events” is vital to the defense of the nation.  Missile launches are serious business and DEFSMAC provides the earliest possible indications and warning of  such a potential threat.  The DEFSMAC times, alone, are sufficient to establish the impact times of the four hijacked aircraft.

In the end

We spent considerable time running the seismic issue to ground.  Yet the answer did not matter, it wasn’t the “right” answer.  During the reading of Staff Statement 17 at the final air defense hearing we presented the list of sources for 10:03 time of impact for UA 93.  Behind us, someone in the audience commented, what about the seismic data?

Questions answered that don’t provide the expected or wanted answer become…more questions.

9-11: UA 93; headed for Washington National

The purpose of this brief article, published under the UA 93 category, is to document primary source information concerning the new flight plan for UA 93 with destination Washington National.

The audio file was recorded at Position 14C, Herndon Center, on a tape with the title: 5 DCC 1933 Ops Phone 5140, Position 14C 1315-1415 UTC.  That position received a call at 10:04:25 after UA 93 was down asking if the Command Center had the “strip” on UA 93.  The unidentified caller reported a call from New York Center that the plane departed Newark and was “inbound to Washington National.”

That call confirms that the new flight plan and destination for UA 93, as entered in the system by Cleveland Center, was available in the Traffic Display System.

The conversation can be heard on this clip. 100425 UA 93 Headed to Washington National

9-11: UA 93; airphone call, not a cellphone call

This short article provides an example of how the terms “airphone” and “cellphone” became conflated and confused right from the first reports of use.  The pertinent conversation was recorded at Operations Position 28, Herndon Center, a few minutes after 10:00.

Great Lakes Region security notified the FAA Tactical Net of a report from the Oak Brook, Illinois, police that they had received a 911 airphone call from a passenger aboard UA 93 reporting three hijackers with knives and making bomb threats.

Concurrently, in the background another individual passed the information to someone else and substituted the word “cellphone” for “airphone.”  That conflation occurred as the report was received by the Tactical Net.

The audio of those conversations can be heard here.  100310 Airphone Call UA 93

A report that the White House, Treasury and State are being evacuated can be heard in the background at the beginning of the audio clip.  The time was 10:03, so that was a delayed report.  BBC video footage from “Clear The Skies” established that the White House evacuation began sometime after the Pentagon was struck, but  before 10:00.

9-11: UA 93; an air traffic control trilogy, part 2

Addendum, December 1, 2009.

Here is a Google Earth plot of the final radar returns from UA 93 as received at The Plains radar site and provided by 84th RADES.

UA93 Final Radar Returns
UA93 Final Radar Returns

The blue pins depict primary returns.  The green pin depicts the first recording of the transponder back on.  Green represents a reinforced return, radar and beacon (transponder).  The red pin depicts the second and final transponder return, beacon only.

This is the air traffic control story of UA 93, told in the primary source voices of the day, and we begin with part 2, the Herndon Command Center story.  The next two articles will tell the same story from the Cleveland Center (ZOB) perspective,  Part 1,   Then, in Part 3, we will the FAA’s Washington Operations Center story, as told to them by air traffic control.  There will be at least one additional article to tell the story after it leaves the domain of air traffic control.

First notice to Herndon

The story begins at 09:49 when Margaret at the Herndon Severe Weather position convenes a conference with Washington Center, ZDC, at the request of Cleveland and Chicago.  The purpose is to address the issue of the Attorney General’s return to Washington.  Cleveland breaks in to tell Chicago about Delta 1989.  That conversation is at this link. ZDC ZOB Herndon Chicago Teleconference

The conversation immediately continues and by 9:50 Cleveland Center has also put Washington Center on alert but about a different airplance, UA 93.  That continued conversation is at this link.  ZOB alerts ZDC about UA 93

After a short pause ZOB estimates a UA 93 arrival in 25 minutes to Dulles (approximately 9:16).  Concurrently, ZOB updates both Chicago and ZDC as to the status of both D 1989 and UA 93.  That continuation is at this link.  ZOB updates D 1989 and UA 93

Some researchers have speculated that FAA was treating one of the two aircraft but not the other as a hijack; that the two were somehow confused by air traffic control.  It is clear from the primary source information that the two situations were distinct and clearly separated by Cleveland Center in its reporting to adjacent centers and to Herndon.  There was no confusion within the system as to which was which.   The status of D 1989 was never conflated with UA 93 by FAA.

Conversation continues at 09:53

The situation continues as ZOB updates all participants on the status of both airplanes.  Margaret informs ZOB that Herndon knew about UA 93 but not about D 1989 and she will pass the word.  That update can be heard at this link.  ZOB Undates Participants at 0953

D 1989 apparently resolved

In a conversation at 9:56 Herndon determines that D 1989 is not a ‘trip,’ that he is fine and that he is going to Cleveland.  In this conversation we learn that the concern about D 1989 originated with Boston Center, ZBW.  That conversation can be heard at this link.  ZOB D 1989 Going to Clevelend

Real time updates on UA 93

By 9:58 ZOB enters a new flight plan for UA 93 to assist ZDC.  ZDC acknowledges and sees the airplane at their TMU desk.  ZOB is trying as best it can to associate tracking information with the data blocks.  They did not have an altitude.

The implication is that ZDC can see the plane on radar as long as it is flying and can track the flight plan on a TSD display.  The exchange of information between the TMU at ZOB and the TMUat ZDC can be heard at this link.  ZOB UA 93 new flight plan and alert to ZDC.  I should note here that when I observed the TSD playback of 9-11 at Herndon Center the icon for UA 93 visably jumped on the screen to its new location as determined by ZOB.

Shortly thereafter, in the 9:59 time frame,  ZOB did obtain altitude information on UA 93 from a VFR aircraft.  That information can be heard at this link.  ZOB reports altitude on UA 93 Whenever Ricky Bell at Severe Weather keeps the microphone open you can hear voices in the background.  We will cover that in Part 3 when we talk about Herndon continuously updating FAA Headquarters.

Next, ZOB provides altitude and heading information in real time to Herndon.  You can, again, hear voices in the background and you hear Ricky Bell repeating information as he hears it so that others at Herndon are aware.  This minute long conversation segment  begins approximately 10:00 and can be heard at this link.  ZOB provides location and heading for UA 93

From 10:01 to 10:02 the real time updates report erratic flying.  That near one minute conversation segment can be heard at this link.  ZOB reports erratic flying

UA 93 transponder back on

The UA 93 transponder did come back on, briefly for two sweeps just  before 10:03.  84th RADES radar lost coverage on the plane soon after 9:47, but reacquired the aircraft near the end of its flight.  Radar data from The Plains radar shows the transponder back on for just two radar returns.  Based on those two returns the aircraft dropped at a significant rate.  It was in extremis.  The last recorded RADES radar return is at 10:02:57 at 6100 feet altitude.  Location was 40 040 04N 78 55 02W.

ZOB describes the transponder event to Herndon as heard on this link.  ZOB Reports Transponder Back On.  The ZOB report is time consistent and altitude consistent with RADES radar.  ZOB reports an altitude of 8200 feet when the transponder came back on.  The RADES radar files show an altitude of 7800 feet at that time.

Here is a circa Summer 93 graphic I prepared concerning UA 93.  My complete set of UA 93 powerpoint slides has been uploaded to the History Commons Scribd site; I can’t find the link for now, and is available at this link.

UA 93 Final Radar Returns
UA 93 Final Radar Returns

UA 93 lost by ZOB

Just before 10:03 ZOB reports losing UA 93 on radar except for one primary return.  ZOB defers to ZDC as can be heard at this link.  ZOB losing UA 93 on radar

A few moments later Herndon reconnects with ZOB to ask about both UA 93 and D 1989.  Herndon learns that ZOB has lost UA 93; it was last headed toward Washington.  Herndon also learns at the same time that D 1989 is not a hijack.  That exchange can be heard at this link.  ZOB advises UA 93 lost D1989 not a hijack

And, to finish off part 2 of this trilogy, at 10:10 ZOB and Herndon have a concluding converstion that reaffirms that ZOB has lost UA 93 on radar and that D 1989 is not a hijack.  This conversation segment provides additional insight in how Herndon was operating and what it knew.  ZOB Herndon Discusses Both Planes

Observations in real time

First, at no time at the desk level, do air traffic control personnel speak to or even mention contacting the military.  That is to be expected, their job was to track and report.

Second, at no time did Herndon or ZOB conflate information concerning UA 93 and D 1989.  Both planes were monitored distinctly and separately and reported that way.  FAA up to the Herndon level had situation awareness in real time.  Researchers who argue differently are simply wrong.

Third, separately, ZOB is learning of the fate of UA 93 and we will discuss that in Part 1 of this trilogy.  For now, the embedded graphic provides useful data points.  Gofer 06 soon after turning north at ZOB direction reported shortly after 10:04 that the pilot saw smoke in the direction of UA 93.  The private jet, N20VF? on the graphic, was vectored by ZOB to the crash site.  The Falcon circled once and provided GPS coordinates around 10:14.

Finally, at the national level. Norman Mineta is arriving at the PEOC during the final moments of UA 93.  Subsequently he will receive information from Monte Belger about that aircraft, most likely as seen on a TSD display.  That track, terminating at Reagan National at 10:28 is a ghost and has been since shortly after 10:03.

That begs a question.  Given that Herndon had near real time information and was immediately passing that information to FAA Headquarters, how was that being passed, if at all, to the national level?  We will grapple with that in Part 3.  For now I would simply point out that the SVTS link was activated at 9:25 and Richard Clarke convened the conference soon after 9:40.  He wrote in Against All Enemies, “Okay, I began.  Let’s start with the facts.  FAA, FAA, go.”  Jane Garvey was at the FAA end.

What do we make of that?

I am separately publishing articles on the linear processes the government attempted to use that day.  So far I have spoken to NOIWON.  Once I get an Air Threat Conference article out I will then turn to SVTS.  Suffice it to say for now that, as I’ve elsewhere attributed to an NMCC staff officer, the SVTS process was counter-productive.

So, I will speak to SVTS, probably before I write Part 3 of this air traffic control trilogy concerning UA 93.

At some point, of course, we will ultimately need to address the Mineta story.