List of United 93 Airfone calls

 

The above list is an excerpt of a  9/11 Commission paper on the GTE airfone calls. For a better view click  here.

Airfone is a terrestric system. The calling passenger is connected to the recipient via a net of ground stations (RBS=radio base station) scattered over the country. They connect the caller with the dialed number via landline. If the plane moves from one RBS area to the next, a handoff takes place, similar to cell calls. So in general, the position of a plane can be determined by the RBS with a decent uncertainty, just like VHF ACARS messages. Because the net of RBS is more wide-meshed than the net of ARINC RGS, the uncertainty is even bigger. Nevertheless, the list delivers valuable position information.

For each call, the list denotes (among other things)

- the name of the caller, 

- the seat where the call was placed from

- the begin of the call
- the duration of the connecting process

- the duration of the actual call

- the RBS at the begin of the call

- the RBS at the end of the call

- the number of handoffs during the call

The meaning of the columns (first row) is explained here:

http://media.nara.gov/9-11/MFR/t-0148-911MFR-00216.pdf 

For instance the last column - SCP duration,  "Switch Control Processor" - indicates the time (in seconds) the call was connected to the dialed number. For United 93, only four RBS were involved, and each of them has an ID number: Columbus (59 - "Colombus" with a typo), Fort Wayne (26), Belleville near Detroit (91) and Coraopolis near Pittsburgh (65).

The list makes it possible to determine the time and RBS when the call was commenced as well as the time and RBS when it was disconnected.

     Caller         Seat      Begin of Call         End of Call         # Handoffs

                             Time       RBS        Time    RBS     

Thomas Burnett     24ABC   9:30:32  Fort Wayne   9:31:19  Columbus     *

Flight Attendant   34ABC   9:32:39  Fort Wayne   9:34:17  Fort Wayne 

Flight Attendant   34ABC   9:31:14  Columbus     9:31:34  Columbus

Flight Attendant   33DEF   9:35:40  Detroit      9:41:45  Fort Wayne   *

Flight Attendant   34ABC   9:35:48  Detroit      9:37:32  Detroit

Flight Attendant   33ABC   9:35:58  Detroit      9:37:42  Detroit

Mark Bingham       25DEF   9:36:10  Detroit      9:36:51  Detroit

Mark Bingham       25DEF   9:37:03  Detroit      9:40:05  Fort Wayne   *

Jeremy Glick       27DEF   9:37:41  Detroit     11:44:00  Pittsburgh   ********

Thomas Burnett     25ABC   9:37:53  Detroit      9:39:19  Detroit

Lauren Grandcolas  23DEF   9:39:21  Detroit      9:40:21  Detroit

Lauren Grandcolas  23DEF   9:40:42  Detroit      9:41:04  Detroit 

Mark Bingham       25DEF   9:41:20  Detroit      9:41:36  Detroit

Lauren Grandcolas  23DEF   9:41:34  Columbus     9:41:52  Columbus

Mark Bingham       25DEF   9:41:53  Detroit      9:42:29  Detroit

Lauren Grandcolas  23DEF   9:42:03  Columbus     9:42:19  Columbus   

Joseph de Luca     26DEF   9:42:13  Columbus     9:42:47  Columbus

Lauren Grandcolas  23DEF   9:42:25  Columbus     9:42:41  Columbus

Todd Beamer        32DEF   9:42:44  Detroit      9:42:48  Detroit

Todd Beamer        32DEF   9:42:44  Detroit      9:43:29  Detroit 

Lauren Grandcolas  23DEF   9:42:45  Columbus     9:43:02  Columbus

Joseph de Luca     26DEF   9:43:03  Columbus     9:45:28  Columbus 

Lauren Grandcolas  23DEF   9:43:24  Columbus     9:43:31  Columbus

Lauren Grandcolas  23DEF   9:43:44  Columbus     9:44:16  Columbus  

Todd Beamer        32DEF   9:43:46  Detroit      9:43:49  Detroit

Todd Beamer        32DEF   9:43:48  Detroit     10:50:20  Detroit      ******

Thomas Burnett     25ABC   9:44:23  Columbus     9:45:37  Columbus

Waleska Martinez   34ABC   9:45:37  Columbus     9:47:55  Columbus

Linda Gronlund     26DEF   9:46:05  Columbus     9:47:44  Columbus

Ceecee Lyles       32ABC   9:47:57  Columbus     9:49:28  Columbus

Joseph de Luca     26DEF   9:48:48  Columbus     9:48:57  Columbus

Marion Britton     33ABC   9:49:12  Columbus     9:53:01  Pittsburgh   ***

Sandra Bradshaw    33DEF   9:49:30  Columbus     9:49:45  Columbus

Sandra Bradshaw    33DEF   9:50:04  Columbus     9:58:27  Pittsburgh   ***

Honor Wainio       33ABC   9:53:43  Pittsburgh   9:58:23  Pittsburgh

Here is a map of all RBS in 2006 (Source).

It is unclear whether all of these RBS were operative in 2001. According to this source f.i., the Cleveland RBS was not operative in 1991. This might explain why Cleveland doesn't appear on the airfone call list. The list will certainly shed a better light on the story of the "heroes of United 93". More research is forthcoming.

United 93 received 18 ACARS uplinks after alleged Shanksville crash: CONFIRMED

 

  "Man, that ain`t rocket science...  ein zertrümmertes Fax in einem Erdloch bei Shanksville sendet kein Handshake."

Kesha, administrator 911-archiv.net

 

 

The state of affairs 

 

The historical "Operation Northwoods" plot is viewed by many as a paradigmatic blueprint for the 9/11 attacks: the original four planes were replaced by drones and landed at secret locations while the drones were directed into their respective targets. It is possible to reconstruct the flight route of a plane by its radar data, but radio records from air traffic control and ACARS messages are fundamental tools for this purpose, too. Needless to say, these three data sets should coincide 100% in order to exclude a plane swap scenario à la Operation Northwoods. But they don't. For example, controllers were tracking Flight 11 still after the North Tower crash, so we have a contradiction between ATC radio talks and the RADES radar data. And then there's ACARS.

ACARS - Aircraft Communications and Reporting System - enables an airline to track its planes independently from radar, because every message, uplink or downlink, is routed via a certain ground station, and the station is recorded and denoted in the message. So it's possible to determine where the plane has been when the message has been sent, albeit with a pretty uncertainty of up to ca. 70 miles. The ACARS branch of  9/11 investigation has its own history by now. I myself started it in 2009 (1). In 2011 Rob Balsamo of pilotsfor911truth.org published additional corroborative evidence in two articles (2, 3). In 2012 Italian researchers started a website especially dedicated to ACARS (4).

The ACARS case was originally based on two documents: a printout of ACARS messages sent by United Airlines to United 93, United 175, and other planes (5) - from now on referred to as UAL printout - and the comments of Michael Winter, a United dispatcher who perused the messages to United 93 in the course of a FBI interview (6). These two sources show consistently that the flight path of United 93 followed a route Pittsburgh-Cleveland-Toledo-Champaign/Indiana, which is obviously different from the official route. Moreover, they show that United 93 was still airborne at 10:11. This is being discussed extensively in the mentioned articles.

In response to Balsamo's articles, 9/11 researcher Warren Stutt published another document, obtained by an FOIA request: the ACARS records of ARINC (Aeronautical Radio Incorporated), the company that manages the communication between the airlines and their aircraft (7). The file reveals that uplink messages follow a three-step process. When the dispatcher is finished with typing in the message and pushes the "send" button, a ULMSG (Uplink Message) is sent to a certain ARINC ground station via landline (ground-to-ground). The message is then converted into one or more ULBLK (Uplink Block) and sent to the plane (ground-to-air). The plane's data processor then checks if the message has been completely and correctly received. If so, the plane acknowledges the receipt of the message with sending a DLBLK (Downlink Block) to the ground (air-to-ground).

Despite the lacking data for United 175, the file looks authentic and matches nearly perfectly the UAL printout and the FBI/Winter interview regarding Flight 93 - with a few remarkable exceptions. I have expressed my objections in my last blog entry (8). So we have four official sources with diverging position data for United 93:

Time	Official Version	FBI/Winter Interview	UAL Printout	Stutt ARINC File
9:22	Pittsburgh	Pittsburgh	Pittsburgh	Pittsburgh
9:32	Canton/Akron	Canton/Akron	Canton/Akron	Pittsburgh
9:36	Cleveland	Cleveland	Cleveland	Pittsburgh
9:50	Pittsburgh	Toledo	Toledo	Pittsburgh
10:11	crashed	Champaign	Champaign	Pittsburgh

The publishing of the ARINC file ignited a fierce debate on diverse forums (9, 10, 11, 12). Stutt's bottom line is that the ARINC file refutes the findings of Balsamo, Sergio and myself. But it doesn't - the case is a little bit more complicated.

1 - The ULMSG's in the ARINC file correspond nearly one-to-one to the messages of the UAL printout. Stutt states correctly that the position data in the printout are no direct proof that United 93 was in the vicinity of the respective ground station because the ULMSGs are only ground-to-ground transmissions. Stutt goes so far as to claim that the position data reflect the plane's predetermined flight plan only and are not adjusted when the plane changes its route, i.e. there is no correlation at all between the position in the printout and the plane's actual position. But this is an unproven claim.

2 - Unlike the UAL printout, the FBI/Winter Interview deals with ground-to air and air-to-ground messages. The table shows fundamental discrepancies between the ARINC file and Winter's testimony after 9:30. Stutt declares Winter to be in error, which is a bold step considering the dispatcher's professional expertise and the fact that David Knerr, United dispatch manager, was present during the interview and provided confirmation.

3 - The table also reveals fundamental discrepancies between the ARINC file and the official story between 9:30 and 9:40 when United 93 made its U-turn over Cleveland. According to the ARINC position data, the plane ceased flying westwards and instead circled over Pittsburgh after 9:23. Stutt tries to explain away this problem by claiming that the Cleveland and Canton/Akron ground stations were not tuned to the proper frequency, but this assertion doesn't stand a critical examination (13).

4 - Regarding the crucial messages to United 93 after the Shanksville "crash", Stutt states that the plane didn't receive them because they were not acknowledged: "Also the file shows that there are no type DLBLK blocks and therefore no ACARS messages received from UAL93 after the official time of the crash." (9, post #85) Mr. Stutt seems to believe that every received uplink is inevitably acknowledged by the aircraft, so if a message is not acknowledged, it has not been received. This, however, is not true. A plane may receive an uplink, while ground control doesn't receive the acknowledging downlink.

This article will concentrate on point 4.

The last seven messages for United 93 

This is what United Airlines dispatcher Winter told the FBI regarding the last seven messages - all of them sent long after the alleged crash at Shanksville (6 - scroll down to the end):

Here are the relevant details for messages #18 to #24 from the Stutt ARINC file in an edited form.  For convenience, the list omits all non-relevant data and features only the type of message and the time it was generated:

All seven messages are not acknowledged and end up in error reports (ICPUL="Intercept Protocol Uplink"). But for #18 and #19 there are nine ULBLKs, re-sent every 10 seconds due to the missing acknowledgment while messages #20 to #24 were rejected outright - no uplink at all. Also #18 and #19 have a different error reason code (ICPUL 311) than #20 to #24 (ICPUL 231). ICPUL 231 indicates an immediate rejection, whereas ICPUL 311 is only generated after nine unacknowledged uplinks.

For some reason Winter seemed to know that ULBLKs are aired only if the addressed plane is within radio range - i.e. that a sent ULBLK implies a received ULBLK. This is confirmed by his colleague, United dispatch manager David Knerr, who was present during the interview. Two weeks later, Knerr himself was interviewed by the FBI - obviously the investigators had still some pending questions regarding the last messages of United 93 (14):

Knerr explained the uplink and downlink references on an ACARS message. DLBLK refers to downlink while ULBLK refers to uplink. These references also identify that a ACARS message has been received by its sender, either ground communications or the aircraft.

The first thing to note here is the paradox phrase "received by its sender". The second thing is that Knerr is cited indirectly and certainly did not use this formulation word by word. It's so strikingly nonsensical that an ordinary interrogator would have reacted with "what did you say?" or "what do you mean by that?", giving Knerr the opportunity to correct or clarify the statement. Finally the writer of the the summary must have overlooked the phrase. Such three-fold blunders don't use to happen in the real word. Knerr certainly did not say verbatim "received by its sender". But what did he say then?

Without the "by its sender", the sentence makes perfectly sense: These references also identify that a ACARS message has been received. In other words: a sent ULBLK/DLBLK is always a received ULBLK/DLBLK. Other interpretations of the errant phrase are hard to envisage. Maybe the significance of Knerr's account was so explosive that someone inside the FBI felt the need to obfuscate it by inserting the illogical addendum.

Nigel J. Lee, Boeing avionics engineer, corroborates Winter and Knerr in an appendix to the ARINC 618 Air-Ground-Protocol (15, p. 133):

According to Lee the MU (the aircraft's ACARS Management Unit) is able to determine whether the plane is out of radio range or something else is the reason for the missing acknowledgment. This is only possible if the downlink message is preceded by some kind of "link test" - is there radio contact to the ground? - and only sent if the test turns out positive. If it turns out negative, the MU instantly determines a NO COMM situation. If the link persists, but the downlink is not acknowledged, the system retries to downlink the message up to six times before it generates the NO COMM error message. So the routine for a no-radio situation differs from the routine for other unacknowledged messages.

ACARS 618 is written for manufacturers of avionics equipment and generally describes the downlink routines. But it is emphasized several times that the same rules also apply to uplinks. So it's safe to say that uplinks have such a preceding link test too, and this is why Winter and Knerr knew that a sent ULBLK is always received by the plane: it has successfully passed the link test. Without passing the link test, no ULBLK is sent.

The elucidations of these three experts justify postulating a link test which precedes the transmission of the actual message. We now have to consider the technical side of ACARS transmissions. The link test exists, and it has a name. Communication engineers colloquially call it a "handshake".

The ACARS handshake 

 

ACARS is, like Telefax, an offspring of the old Telex system. Each Telex transmission is initiated by a so-called handshake: a synchronization process between sender and receiver to enable and optimize the transmission of the actual message. This requires an exchange of data between sender and receiver before dispatching the message. The designers of ACARS have adopted this principle (16): "Upon receiving a message, the DSP ((ground system)) 'handshakes' with the aircraft Communications Management function according to the ACARS air-ground protocol."

The handshake is exactly the kind of link test we're looking for. If the plane is out of radio range, the handshake will fail, and the uplink message cannot be sent. Conversely: a sent ULBLK implies a successful handshake; a successful handshake implies a good VHF connection; a good VHF connection implies that the plane is within line-of sight or at least almost line-of sight of the ground station; and a line-of-sight condition implies that the plane is airborne (exception: the plane is grounded at the airport where the sender is sited - but this was not the case for United 93 at 10:11). This causal chain is hard as diamond. A crashed smouldering plane is certainly not able to response with a handshake when it is contacted by ground control.

The ARINC 618 protocol provides technical details. ACARS is a "halfduplex" protocol (15, p. 139): ground system and plane communicate via a two-way radio channel, i.e both of them can send and receive, but not at the same time. Every ACARS message, uplink or downlink, is initiated by a so-called preamble. The preamble is the ACARS handshake. It consists of three parts - pre-key, bit synchronization, and character synchronization (p. 21). The data link is established using a technique called Minimum Shift Keying (MSK) (p.22):

In other words: during the pre-key phase,  sender and receiver create in a two-way process the physical preconditions (phase coherence) for the data transmission. The synchronization is then refined during the bit sync and character sync phases. Avionics people jestingly say that ground and airborne system "play ping-pong" (2).

So if the sender of an ACARS message, uplink or downlink, doesn't receive a handshaking response from the addressee, the system knows that there is no radio contact and it's hopeless to send the message. The transmission process is aborted. ARINC 618 describes what happens in the case of a failed downlink handshake - the MU goes into NO COMM status (p. 26):

To sum it up: ARINC 618 provides first hand evidence that ULBLKs are only sent when the preceding handshake is successful, which proves that United 93 physically received the last 18 uplinks. I'm using the term physically received  here in the sense that the begin of the message - the handshake - has been received as distinct from contentually received for a message that has been received in its entirety. This distinction is important, and I will get back to it in the appendix. The first definition is weaker than the latter, but for our reasoning it's absolutely sufficient. If United 93 has received the 18 uplinks physically, it was airborne, even if it hasn't received them contentually because they were corrupted by interfering signals or something else.

Warren Stutt's assertion that these 18 uplinks were not received physically because they were not acknowledged is simply wrong. This raises the question why they were not acknowledged. As important as an answer to this problem certainly is, it's not mandatory for the basic result of my argumentation: a sent ULBLK indicates that the addressed plane is airborne. Therefore I will postpone the answer and propose a lucid solution in the appendix.

The key: Source authenticity 

When it comes to the question whether United 93 has received messages #18 and #19, the Stutt ARINC file not only confirms Winter's statement and the UAL printout, but even grants a better insight thanks to the myriads of detailed data. It is even able to explain why message #20 looks different than message #24 in the UAL printout: message #20 was stuck in the output buffer for over two minutes, because it had to wait for the repeated uplinking of message #19. In contrast to that, messages #21 to #24 were rejected outright because the output buffer was empty.

This positive finding is encountered by the strange flight path of United 93 as documented in the ARINC file. It is not only in conflict with Winter and the UAL printout on the one hand and with the official story on the other hand. It also makes us believe that United 93 circled over the Pittsburgh area since 9:23 for at least 50 minutes. This scenario is not only utterly unrealistic, there's also not the least hint for it in the many published ATC radio correspondences either. Certainly the file has no good cards here. Moreover, the missing data for United 175 raise grave suspicion. An excellent article of Sergio (17) delivers some lucid reasons why the data were not released.

Given these ambiguous conditions, what value has the Stutt ARINC file for solving the criminal case of 9/11? Should it be discarded, or should it be taken at face value? Objectively, there are three possible modes to deal with it:

1 - The Stutt ARINC file is 100% genuine. Warren Stutt himself abstains from commenting its authenticity on his website, but from the efforts he's undertaken to bring it to the people and diverse comments on diverse forums, this seems to be his position. But then he has to admit that the file is in conflict with the official story regarding United 93's whereabouts around 9:35 and also that it received 18 uplinks ten minutes after the official crash time, wherever it was flying around.

2 - The Stutt ARINC file is completely manipulated, and it makes no sense to try to gain information out of it. Proponents of this position don't take account of its authentic character however (correct ACARS syntax etc.), as well as the deep correspondence with other well-known and unquestionable sources. Thereby they squander a powerful tool to clarify the fate of United 93, American 11 and American 77. They have also to explain why the fakers took the trouble to "invent" the 18 ULBLKs sent to United 93 after its alleged crash.

3 - The Stutt ARINC file is in part manipulated; apart from the obviously forged position data of United 93 after 9:23 however, no other irregularities have been detected so far.

In my opinion 3 is definitely the most rational choice. The Stutt ARINC file has a paramount historical significance despite its flaws and should enjoy top priority if a reinvestigation of 9/11 once sees the light of day. The dispatchers Ed Ballinger, Michael Winter and David Knerr should be among the very first people to consult.

Sources

 

1 - United Airlines tracked a different Flight 93 than the FAA (Woody Box)

2 - ACARS confirmed - 9/11 airborne long after crash (Rob Balsamo)

3 - It is conclusive - 9/11 aircraft airborne well after crash (Rob Balsamo)

4 - 911acars.blogspot.com

5 - UAL Printout

6 - FBI Interview with Michael Winter

7 - Stutt ARINC file

8 - Open Letter to Warren Stutt re: ARINC logs (Woody Box)

9 - Pilotsfor911truth.org ACARS thread

10 - Unexplained-Mysteries.com thread p.116+++

11 - Return to Sender (booNyzarC)

12 - JREF forum thread

13 - Analysis of United 93 U-turn over Cleveland based on the ARINC logs (Sergio)

14 - FBI Interview with David Knerr

15 - ARINC 618-5-2000 Air-Ground Protocol

16 - Boeing Avionics Manual

17 - Ed Ballinger and the uplink sent to United 175 at 9:51 EDT (Sergio)

Appendix: CSMA and the hidden transmitter problem 

 

Warren Stutt's assertion that United 93 did not receive the last 18 uplinks is not tenable. But what happened to them - why have they not been acknowledged? I've already stressed that an answer to this question is not requisite for the main thesis. Nevertheless I will now propose a simple solution without claiming to have found final proof.

CSMA (Carrier Sense Multiple Access) is a technique used in communication technologies dealing with the situation that one single data carrier (or data bus/data channel) is shared by several users to exchange messages, but is only able to convey one message at one time because two simultaneous messages disrupt each other. Therefore a user must check ("sense") if the channel is clear, i.e. no transmission is occurring, before dispatching a message. If it's not clear, the user has to wait a couple of milliseconds before checking the channel again. This procedure is repeated until the user finally senses a free channel and thus gets the okay to send the message.

This is the basic CSMA algorithm. There are more sophisticated versions like CSMA with Collison Avoidance and CSMA with Collision Detection but "Plain Old ACARS", which was in effect on 9/11, uses basic CSMA. The carrier is a "very high frequency" (VHF), and the users are, of course, ground stations and planes. If a ground station senses that the channel is occupied, it waits for a randomly chosen time (between 30 and 300 milliseconds according to ARINC 618) before trying again.

Basic CSMA suffers from a fundamental hitch with a sizeable impact on ACARS, making it even slower than it is already. It's called the hidden transmitter (or hidden node/hidden station/hidden terminal) problem.

Diagram 1 illustrates this situation: two ground stations A and B are separated by a mountain. If A wants to send a message and checks the frequency while B has already started a transmission, A will not sense B's transmission: B is a hidden transmitter. The system will conclude that the channel is free and A transmits the message. This will result in a collision of the two transmissions and corrupt at least one, if not both of them, depending on the relative strength of the signals. The addressed plane will not send an acknowledgment to A because it did not receive the complete message. After 10 seconds, A will try to resend the uplink, check the frequency, and so on.

Diagram 1

Hidden transmitters generate corrupted messages, and corrupted messages are not acknowledged. So they might well have been the reason for the 18 unacknowledged ULBLKs. We have to discern two cases: the ULBLK was corrupted and the plane didn't send an acknowledging DLBLK, or the acknowledging DLBLK was corrupted. In the first case UA 93 didn't receive the ULBLK contentually, in the second case it did. But in both cases it received the ULBLK physically, making both of them toxic for the official UA 93 version.

If a plane is flying high, at cruising altitude, it is certainly within line of sight of all ground stations and planes in the vicinity, so downlinks can't bump into transmissions from hidden transmitters, but uplinks are prone to them. This case is shown in Diagram 1.

A statistical analysis of the Stutt ARINC file (comprising all three planes) shows that as much as 32% of all ULBLKs based on an ULMSG had to be resent after 10 seconds because they were not acknowledged. I factored in all ULSMGs from 15 minutes after take-off until the first error messages (exclusively), so in most cases the plane was certainly flying at cruising altitude.  Here's the result:

Overall number of ULMSG: 29
ULBLK acknowledged at 1st attempt:  18
ULBLK acknowledged at 2nd attempt:  9
ULBLK acknowledged at 3rd attempt: 1
ULBLK acknowledged at 4th attempt: 1
Overall number of ULBLK: 43
Overall number of unacknowledged ULBLK: 14

This shows that hidden ground stations jamming uplinks is a common, inherent flaw of Plain Old ACARS.

Diagram 2

Diagram 2 shows that the situation changes drastically when the plane is flying low. The lower the altitude, the bigger the probability that the line-of-sight to any ground station is blocked by terrain. So this situation generates hidden transmitters for downlinks. Conversely the probability that uplinks suffer from hidden transmitters decreases. This is because at low altitude, the line-of-sight between the plane and a potential hidden transmitter for the sending ground station may be blocked. The hidden transmitter turns into a "no transmitter" and is no gadfly for the station anymore. In the extreme case that the plane is in radio contact with only one ground station, this station has a 100% chance of success to uplink a message, while the chances of success for a downlink is very small due to the potential big number of ground stations functioning as hidden transmitters.

Besides of message #18 and #19 for United 93 there are five more messages in the Stutt ARINC file ending up in an ICPUL 311 NO ACK message after a sequence of several (usually 9) unacknowledged ULBLKs: one for American 77, and four for American 11. Interestingly, the first two ICPUL 311 (after 9 resp.10 repeated ULBLKs) for American 11 occurred when the plane was idling at the gate, between 7:30 and 7:35. Here's an outprint of the second one. - note the similarity to the ICPUL 311 at the beginning, which belongs to message #18 for United 93.

Apart from Boston, it was certainly out of line-of sight of any other (potentially jamming) ground station. So an ULBLK sent from Boston to the plane had probably a 100% chance  to come through. This makes corrupted DLBLKs the best explanation for the missing acknowledgments. In all probability another plane idling at a distant corner of the airport and blocked by several buildings jammed American 11's DLBLKs. Does this case help explain what happened to messages #18 and #19 for United 93?

Another odd quote from David Knerr gives a valuable hint: "In the final moments, at 10:12 AM EST, of UA Flight 93's flight, ACARS messages were being sent from ground communications but were not being received. This was causing the ACARS messages to be rejected. Knerr advised that Flight 93's low altitude may have caused this dilemma or the fact that Flight 93 had already crashed at the time messages were sent."

The crash at 10:03 was viewed as a fact. There's absolutely no need to mention the alternative possibility that United 93 was flying low - why is it mentioned then? Again we have to read between the lines. The fact that the "low altitude" remark made it into the final FBI report makes only sense if Knerr, the ACARS expert, professed himself unable to explain messages #18 and #19 by a crash and proposed a better solution: the plane's low altitude. Which fits perfectly the model of Diagram 2.

Knerr's statement together with the similar appearance of the grounded Flight 11 suggests that the 18 ULBLKs were correctly received by United 93, but the acknowledging DLBLKs were corrupted by hidden transmitters as a consequence of the low altitude.

The following diagram is based on ARINC 618 and the Stutt ARINC file and is, with one exception, able to explain the flow of all uplink messages including the rejections. The exception is the ULMSG for Flight 11 which ended up int the above outprinted ICUL 311 at 7:35 - this ICPUL 311 was not generated after 9 ULBLKs, but 10, presumably due to a glitch of the VGC counter.

 

A few explanations:

When the dispatcher releases the ULMSG, it is first checked if the last downlink from the plane happened more than 10 minutes ago. In this case the DSP doesn't know which ground station it has to use for the uplink and generates a ICPUL 231. This doesn't mean that the plane is out of radio range, but it's impossible for the DSP to establish contact because "time has run out".

If the message has taken this hurdle, the CSMA check is performed. In the diagram the check is omitted and it's presumed that the channel is clear.

VGC1 is a transmission counter. It is incremented by 1 each time the ULBLK is sent or resent, i.e. it counts the attempts to transmit it. After 9 futile attempts, the loop is aborted and a ICPUL 311 generated.

After a successful handshake, the ULBLK is sent, and VGT1, the "NO ACK timer" is started or reset.

"ULBLK received" must be understood as received physically.

If the ULBLK is not jammed by a hidden transmitter, the plane's MU initiates an ACK-DLBLK. If this DLBLK is not jammed either, the message routine has been succesfully conducted.

If the DSP doesn't receive an ACK within 10 seconds, measured by the VGT1 timer, a new uplink attempt is initiated.

After the sixth attempt, the transmitting ground station is changed, and after three more attempts, the system generates a ICPUL 311.

Every new uplink attempt requires a new handshake. In case it fails because the plane has moved out of radio meanwhile, the cycle is interrupted and an ICPUL 311 is generated. This apparently happened with the ULMSG of Flight 77 sent at 10:41. It was uplinked only two times.

Open Letter to Warren Stutt re: ARINC logs

Warren,

on your website you have created a special ACARS page, introducing a list of ACARS messages as transmitted through the ARINC data system. You claim that it was obtained via a Freedom of Information Act (FOIA) request to National Archives and Records Administration (NARA).

http://www.warrenstutt.com/ACARSMessages/index.html

As an independent researcher, I welcome your efforts to unveil official documents which might be helpful in answering some of the most urging questions of the official 9/11 story. However, I have some objections regarding the ARINC logs as presented by you. I miss date and number of the FOIA request, and the person who initiated it. Also, I miss a header in the document itself - no reference number, no date, no names which would guarantee authenticity.

There are additional questions regarding the content of the document. Examples: Why are the ACARS data for United 175 missing? Why do the data suggest that United 93 never was in the Cleveland area? And there are more questions begging for an answer.

This being said, I don't want to say that the ARINC logs are completely faked and useless for historical research. Just to the contrary, they match the already known ACARS documents (which I have published here in former blog entrys) in big parts and clarify existing ambiguities. But they create new ambiguities as well.

Intending to make use of the ARINC logs, I'm encountering the dilemma that potential insights are standing on a shaky base and subjected to the sword of Damocles which is called "manipulation". In coming blog entries and articles I will therefore refer to the ARINC logs as "Stutt ARINC logs" to emphasize that their authenticity has not been verified yet. I also will add a disclaimer that my findings are subjected to the insecure authenticity of the document. i.e that I take an "as if" approach: as if the logs were authentic.

I ask you to support my efforts to validate the authenticity of the file by publishing number, date, and inquirer of the document on your ACARS page if possible. If this is not possible, I ask you to publish the reason why not. I also would appreciate a personal assessment of the file's authenticity by you, right on your ACARS page. Do you trust it personally, and are you ready to retract it if its authenticity is thrown into doubt by new developments?


With kind regards,

Woody Box

David Knerr, United Airlines Dispatch Manager, on ACARS

The following interview has been conducted by the FBI on 2/15/2002. I have transcribed the relevant parts. The source URL is here:


http://www.scribd.com/doc/14094164/T7-B11-FBI-302s-ACARS-Fdr-Entire-Contents-FBI-302-s

Knerr provided information related to the printout of text messages transmitted to and from UA Flight 93 on 09/11/2001 through the AIRCRAFT COMMUNICATION ADDRESSING AND REPORTING SYSTEM (ACARS). Knerr identified this system as one means of communication that is utilized between aircraft and commercial carriers, like UA, to transmit text data. Knerr related that data is either uplinked to the aircraft from fixed communication centers or downlinked from the aircraft to receiving communication centers. Knerr explained the uplink and downlink references on an ACARS message. DLBLK refers to downlink while ULBLK refers to uplink.

These references also identify that a ACARS message has been received by its sender, either ground communications or the aircraft. In the final moments, at 10:12 AM EST, of UA Flight 93's flight, ACARS messages were being sent from ground communications but were not being received. This was causing the ACARS messages to be rejected. Knerr advised that Flight 93's low altitude may have caused this dilemma or the fact that Flight 93 had already crashed at the time messages were sent.

Knerr further advised that AERONAUTICAL RADIO INCORPORATED (ARINC) serves as the network administrator for the communication data. According to Knerr, this is important to remember when reviewing data messages because uplink and downlink times may show a time delay when compared. This is caused by multiple processing of multiple ACARS messages through the ARINC network at the same time. ARINC serves a substantial portion of the commercial airline industry operating within the United States. Depending on the time of day or region the country that an aircraft may be operating over, ACARS traffic can be delayed.

Knerr advised that when an aircraft downlinks data to communication towers it does so by sending out messages over a large geographic area that it is flying. Depending on the area of the country, more than one communication tower may receive the aircraft's message. Knerr pointed this out to be the case during Flight 93's flight over New Jersey, Pennsylvania, and Ohio on 9/11/2001.

In addition, Knerr pointed out that on two separate instances during Flight 93's flight on 9/11/2001, prior to crashing in Pennsylvania, two alphanumeric messages were sent from the aircraft to ground communication. These messages were routine maintenance messages that are sent in order to identify the current state of mechanical operations onboard an aircraft during flight. It allows for specialists to view specific mechanical data onboard an aircraft while it is in operation. Knerr advised that these messages, once deciphered, may contain information that would demonstrate that the aircraft was being operated in a manner that was adversely affecting the performance of the aircraft. The analysis of these messages is forthcoming.

The ACARS report provided by Knerr will be maintained in the 1A section of this file. Moreover, this data will also be included on the Newark Investigation Summary, Flight Operations Time Line.

The Cleveland Airport Shell Game: Delta 1989, Delta 1898, United 1898

This short piece is an update of my most popular article so far, "The Cleveland Airport Mystery" from 2004, prominently featured in "Crossing the Rubicon" by Michael Ruppert and "Loose Change, 2. edition" by Dylan Avery.

I examined the circumstances of the landing of Delta 1989, a Boeing 767 out of Boston, at Cleveland Hopkins Airport on 9/11. I was lucky to find so much evidence for the existence of a shadowy doppelganger flight of Delta 1989 - landing at about the same time and likewise being evacuated - that I published the results here.

Unfortunately, many people think the central thesis of the article is that United 93 was the mysterious plane that landed at Cleveland Airport. This ist not true. I never claimed that United 93 landed at Cleveland. For more background, look here.

I claimed, however, and do continue to claim that an unidentified Boeing 767 landed at Cleveland in emergency and was evacuated, with Delta 1989 serving as a cover, i. e. whoever asked for the identity of the mysterious plane afterwards reaped the answer: that was Delta 1989! and stopped asking questions.

In 2009, numerous documents of the 9/11 Commission came to light. There I found a perfect candidate for the eerie double of Delta 1989 - United 1898 - and published it here.

In summary, United 1898 is a most interesting case because Cleveland controllers reported it to a special unit of the FAA, named "AAT-200", which is dealing with accidents, emergency cases and other irregularities. However, on 9/11/2001 United Airlines operated no aircraft with flight number 1898. Together with the salient similarity of the flight number (1989/1898) this makes United 1898 a good candidate for "Flight X" and an interesting matter of investigation.

Two years later, I'm now proud to present an independent verification for the emergency landing of a Flight 1898 at Cleveland. This time it's called Delta 1898.


1009 DAL1989 on downwind at CLE

1024 DAL1989 on ground CLE

1035 Unconfirmed report - DAL1989 flaps up at CLE

1039 DAL1989 parked in secure area/no one exited a/c yet (pilot says he is not being hijacked)

1116 DAL 1898 confirmed by security HIJACK at CLE ATC - communication with pilot does not confirm

1119 DAL 1989 still not suspected hijack; taxiing to terminal

Source

In this internal FAA timeline, there is only one entry for DAL1898. Note that this is definitely no typo because DAL1898 was a confirmed hijacking, whereas DAL1989 (= Delta 1989) was never suspected a hijack, neither earlier nor later than the security warning of Delta 1898. It should be of no big surprise by now that this so-called Delta 1898 was not the official Delta Flight 1898 who was scheduled to depart from Salt Lake City in the afternoon, but - of course - never left the ground on that day.

So United 1898 and Delta 1898 were both fake flight numbers. The identity of the numbers and the similar context (United 1898 was an emergency case; Delta 1898 was a confirmed hijacking) leads straightforwardly to the conclusion that these two planes were one and the same. The close similarity of the flight numbers 1898 and 1989 corroborates the thesis that Delta 1989 functioned as a cover-up for Flight 1898. The plane was probably evacuated as United 1898, was quickly renamed Delta 1898, and fell into oblivion due to the informational cover provided by Delta 1989.

This very much reminds a shell game, with the shells bearing fake flight numbers. And the only entity entitled to legally use fake flight numbers was the military in case of conducting a war game, i.e. an exercise. It appears that the emergency landing of Flight 1898 and its subsequent evacuation was indeed part of a military exercise. This may be the reason why it's so difficult to obtain information about the incident: military secrecy.

Combined with the information already presented in my original article, there is now ample evidence that Flight 1898 was a Boeing 767 of United Airlines coming from Boston - but it was not the regular United 1898. The number of the United Boeing 767's departing from Boston is so small that it should narrow down the search for the identity of the mysterious plane considerably. United 177 looks like a good candidate.

Was Mohamed Atta being employed by American Airlines?

Diane Graney is the second witness (besides Lynn Howland whom I presented in my last blog entry) with precise recollections of Mohamed Atta, but completely ignored by the 9/11 Commission. Graney worked at Portland Airport on 9/11. She didn't see the alleged hijackers Atta and Al-Omari, but recognized Atta's face from the photo that was published in the aftermath. She is positive that Atta, dressed in an American Airlines uniform and able to identify himself as an AA pilot, tried prior to 9/11 to achieve a jump seat on a US Airways flight.

Compare this to the particulars provided by Lynn Howland. According to her, Atta was "wearing a white pilot type or oxford shirt, no tie and blue pilot type slacks" and carried a "really cheap pilot bag". Furthermore, Atta approached her and asked if she was going to fly American 11. Apparently he wanted to jump seat the flight.

Here is a list of persons who occasionally are allowed to take a jump seat in the cockpit (from Wikipedia): In aircraft, jump seats - which are officially termed auxiliary crew stations - can be located in cockpits or passenger cabins. In cockpits, jump seats are provided for individuals who are not operating the aircraft. These might include trainee pilots, off-duty crew members in transition to another airport (see deadheading), government officials (such as Federal Aviation Administration staff), or airline staff.

There are also witnesses in Florida confirming that Atta boasted about his status as an American Airlines pilot. Yet the 9/11 Commission has completely blacked out the accounts of Lynn Howland and Diane Graney and missed to pursue their hints that Atta presented himself on several occasions as an AA pilot in order to jump seat a certain flight.

Was American Airlines aware about Atta's activities? And why has the 9/11 Commission failed to follow this important trace?

Here is Diane Graney's account (date: 9/22/01):

Diane Graney, date of birth ........... employed as a Customer Service Agent CSA and Ground Security Coordinator GSC, U.S. Airways USAIR, Portland International Jetport, 1001 Westbrook Street, Portand, Maine, telephone number 207775-5210, was interviewed at her place of employment. After being advised of the identity of the interviewing agent and the nature of the interview, she provided the following information:

Graney has been employed with USAIR for approximately twelve years. As a CSA for USAIR, Graney's duties include conducting passenger check-ins, checking baggage, making seat assignments, and issuing tickets. She performs her duties at either the USAIR Ticket Counter or at the individual airport gates. As a GSC, she deals with aircraft, airport, and general security issues.

On September 11, 2001, from 5:00 AM to 1:00 PM, Graney was working at the USAIR ticket counter. At some point in her shift she heard of the attacks on the World Trade Center in New York, and that one of the flights was American Airlines Flight 11 out of Logan Airport in Boston. As a GSC, she went and pulled the passenger lists for the US AIR flights to Logan to see if any USAIR passengers had a connection to thje flight. Graney saw that there were two passengers on USAIR Flight 5930 to Logan that had a connection to American Airlines Flight 11. The two names were Mohamed Atta and Abdulaziz Alomari. She also noticed the two were to sit in First Class on American Airlines Flight 11. Graney thought it was suspicious that these two passengers could have taken a better, more direct flight then what they had scheduled.

Graney observed that Atta and Alomari had checked two bags in at the US AIR Ticket Counter, and that Michael Tuohey was the CSA who checked them in. She spoke to Tuohey about the two passengers, and he advised her of what he had observed. She then contacted Chuck Severance, US AIR Station Manager, and informed him of what happened and what she had discovered.

Graney advised that later when she saw Atta's picture on the news, she believed she had seen him before. She thought he may have tried to jump seat once with USAIR, and he was in uniform using an American Airlines pilot identification. She believed that this happened within the last six months. She advised she searched the USAIR jump seat peaperwork to see who had gone through for June 2001, July 2001, and August 2001, but was unable to find Atta's name. She advised the jump seat forms are only kept for 90 days. She became more concerned about this when she heard on the news that some American Airlines uniforms were stolen in Italy.

Graney was then requested to review a photograph array containing twelve pictures of twelve of the alleged hijackers. Graney identified the picture of Mohamed Atta as the person she remembered seeing prior to September 11, 2001 attempting to jump seat a USAIR flight. She also identified the picture of Marwan Alshehhi as someone she had seen sometime at the airport ticket counter. She identified the picture of Waleed Alshehri as someone who looks familiar. Both Graney and the interviewing agent dated and initialed the pictures she identified.

A pilot's strange encounter with Atta at Boston Airport

The following is the official paraphrased statement of an American Airlines pilot, interviewed by the FBI on October 13th, 2001. The witness describes how she was shortly approached by Mohammed Atta inside the AA terminal at Logan Airport. Her account is detailed, credible, and intriguing.

Lynn Marie Florence Howland, First Officer, American Airlines, AA, was interviewed near her home at a Starbucks Café in ................... She was advised of the identity of the interviewing agent and nature of the interview. For identification, she advised that she lives and .............................. and has been with American Airlines for eleven years.

Howland explained to the interviewing agent that she has been out of state for several days flying in her job. To assist her recollection she prepared a type written one page chronology of the events regarding the encounter with a person she thought was the suspected hijacker of AA Flight 11 on the morning of September 11, 2001. She advised that she was extremely tired after her flight. She left her home at approximately 10:00 a.m. all times local on the morning of September 10th, flew down to San Francisco to then fly as first officer for the AA red-eye flight from San Francisco to Boston. Checking a dispatch schedule, she indicated she flew AA flight 198 from San Francisco, California to Boston, Massachusetts. She indicated the flight had a 9:50 p.m. departure, with arrival at Logan Airport, Boston at approximately 6:50 a.m. on the morning of September 11th. The equipment was a Boeing 767. She advised that the captain was Douglas Balmain. She was sure that the arrival gate for her flight 198 was Bravo 33. Subsequently she checked with AA dispatch and was told her flight AA 198 became the hijacked AA flight 11.

After almost everyone had deplaned, she went up the jetway ahead of Captain Balmain. She stated as she was standing near the entrance to the jetway, in the passenger lounge, a male individual comes up to her suddenly and asks if she is going to take this plane out, referring to the flight she just brought in. She said no and he abruptly turned and went and sat down. She thought that was extremely rude. Her first impression was that he was a pilot going to fly in the jump seat. While he wasn't in uniform, he may have been wearing a pilot type shirt, open collar. She thought he may have had a rolling pilot flight kit or bag with him, which she described as black vinyl, round top, and incredibly cheap. Again she could not recall anything else, only at that time wanting to get to the hotel and sleep. She said she was so tired, when she got to her hotel room she crashed in bed, in her uniform. She woke up about one p.m. and then found out about the terrorist attacks. She said for the longest time she wasn't even sure that she was dreaming it all, until she saw photographs of the hijackers in the news, she was instantly sure that the indivdual she saw that morning was the suspected hijacker, Mohammed Atta. She added that when she first saw the pictures of the hijackers in the new media, it was like an electric shock when she saw the picture of Atta.

She described the individual she saw that morning as having dark hair, dark eyes and being approximately five feet, eight inches in height. Because she was so tired and just wanted to get to the hotel, she could not recall much, other than he may have had that cheap pilot flight bag. She could not recall anything else and stated that time she had no reason to notice. She did not think that Captain Balmain would have noticed him. As she explained in her notes, the recollection .... (??? - missing text) She was shown a photo spread of six males and instantly chose number 5, which is the terrorist described as Mohammed Atta. She then signed and dated the photo spread under photograph number five. She said that her selection was based totally on her recollection of the morning of September 11th and not from any subsequent photographs she may have seen in the news.

The following are Howland's notes, prepared prior to the interview and scanned directly into this FD-302 and corrected only for scanning errors:

"Flew flight 198 SF-BOS
Departed September 10
Arrived September 11
On the ground approximately 0650 EST
In gate probably at 0700 EST
I left the cockpit first and waited for the captain at the top of the jetbridge in the boarding area.
He was slower maybe 5-7 minutes behind me.
We went to the hotel. I went to sleep called my parents at 1300 EST and they told me what happened.
Later that day I realized it was the aircraft that I had brought in.
That is what I remembered until I saw the photos on TV.
I was instantly sure I have seen Mohammed Atta before could not remember where.

Two days later I was driving my car in at night in the rain and my thoughts were drifting to the horrible loss. I suddenly had a memory of a man approaching me and asking me if I was taking the flight out. I was stunned. Did this really happen? I thought about it some more and remembered Mohammed Atta approaching me and asking me if I was taking flight 11 out. I said "No, I just brought the aircraft in." He turned his back and abruptly walked away and I was a little annoyed with his rudeness but as it was 0400 body clock time I let it go and told myself that people are rude everyday.

This would have been between 0700 and 0720 EST. I think he was wearing a white pilot type or oxford shirt, no tie and blue pilot type slacks. I am unsure about the shirt but perhaps that was what the man he sat down next to was wearing. I also remember him having a really cheap pilot bag. The vinyl one with a rounded top with black plastic squares at the corners.

I spent 2 days trying to decide of this was a true memory and decided it was. I have decided to share this because I felt it was my civic duty."

http://www.scribd.com/doc/14094195/T7-B11-FBI-302s-Cockpit-and-American-and-Hijacker-Fdr-FBI-302-S-Entire-Contents

This statement creates a huge problem for the official Atta story: According to the BTS database and other sources, it was about 6:00 a.m. EDT when Flight 198 arrived at the gate, not 7:00 EST. (This is a minor mistake of West Coast resident Lynn Howland and in no way damages the accuracy of her other recollections.) Just at this time, a man identifying himself as Mohammed Atta boarded a Colgan Air flight in Portland, Maine, going to Boston. He did not arrive there before 6:45 EDT.

Conclusion: the "Mohammed Atta" whose face was presented on the news in the days after 9/11 and the "Mohammed Atta" in the blue shirt recorded by a security camera at Portland Airport are not the same person. This confirms the outstanding research of John Doe II who has collected plenty of evidence for the existence of - at least - one double of Atta:

http://johndoeii.blog.com/2011/03/29/mohammed-atta

Was Flight 11 a "real world exercise" ?

Source: Newhouse News

In an old Democratic Underground posting the esteemed colleague Shoestring expressed doubts about the customary interpretation of the term "real world" which pops up on the NEADS tapes a couple of times. Here's his quote in its entirety:

The quote of Major James Fox saying, "I've never seen so much real-world stuff happen during an exercise" is really suspicious. I wonder if the staff at NEADS understood "real-world" to mean a live-fly field training exercise, as opposed to a purely simulated command post exercise?

So when Sgt. Jeremy Powell asked Boston flight control center "Is this real-world or exercise?" he could have been asking if the exercise was live-fly or not. And when Boston replied "this is not an exercise, not a test," he took it to mean that it was indeed a live-fly exercise, involving a plane under the control of the military pretending to be hijacked.

This would certainly explain the bizarre conversation between the NEADS "ID techs —Stacia Rountree, Shelley Watson, and Maureen Dooley—when they heard of the reported hijacking:

8:37:56
WATSON: What?
DOOLEY: Whoa!
WATSON: What was that?
ROUNTREE: Is that real-world?
DOOLEY: Real-world hijack.
WATSON: Cool!

I find it hard to believe Shelley Watson would have responded, "Cool!" if she thought "Real-world hijack" did really mean a genuine hijacking. Might she instead have believed it to have meant a "live-fly," with a real plane pretending to be hijacked, for which they could launch fighers in response?

Shoestring surmises that the term "real world" indicates a "live-fly exercise" with real airborne planes as opposed to a "command post exercise" which is only played on the desks and screens of the participating military units. I agree with him that this interpretation is far more plausible than the official version (that "real world" meant an actual, genuine hijacking).

A statement of Lt. Col. Dawne Deskins of NEADS shows that Shoestring is right with his conjecture:

Deskins noted that NEADS had a hijack checklist and a variety of exercises depending on higher authority involvement and direction prior to 9/11. Some of those exercises involved NORAD coordination. She does not recall ever personally designing an exercise in which a decision would be made to shoot down the hij acked aircraft. A typical design would include course deviation in which the hijacker forces the pilot to fly to a designated landing point. They would not do these hijacks exercises real world. They had a cell that would play the FAA in the exercise. Deskins noted that there really were not the assets to do a large scale real world exercise to practice hijack response. The scenarios for the exercises are created by exercise designers in the exercise shop. Sgt. Mark Stanford and Sgt. Mike Quigley, both retired, designed the exercises when she was the head of the shop. NEADS' hijack shop would not design exercises for other sectors.

Exercises that are designed on the NORAD level are created at planning conferences. NORAD planning exercises are mostly held at Peterson, or at CONR at Tindle. There is intelligence representation at the conferences, but the sector shops are more concerned with the individual exercise of the sector floor and Battle Cab. She does not personally recall the design of a hijack with multiple hijacks or terrorist take over.

http://www.scribd.com/doc/19988140/Mfr-Nara-t8-neads-Deskins-Dawne-103003-00778

For the first time, the term "real-world exercise" emerges here in the context of the 9/11 wargames, and according to Deskins, it means a voluminous large-scale exercise with the need to involve the FAA. In smaller (not "real-world" exercises) the FAA was not needed because NEADS had its own cell playing their role. A corollary of Deskins' statement is that real-world exercises were not designed by NEADS itself, but one level above, at NORAD planning conferences.

The reader can easily verify Shoestring's interpretation by searching for "real world exercise", maybe narrowed down with "air force" or "military". The output will quickly convince him that "real world exercise" is a common concept in the military world.

So whenever the term "real world" is used, it indicates that NEADS personnel are believing they are confronted with a large-scale, live-fly exercise with participation of the FAA. NEADS was prepared for these exercises, but not actual, genuine hijackings. It is not known how the air defense used to label such (very rare) genuine hijackings, but it was certainly not "real world" lest to confound it with the ongoing real world exercises.

Flight 11 was apparently viewed as a real-world exercise.

Was Flight 93 part of a military hijack exercise?

FAA delayed alerting of NEADS on the hijacking of Flight 93



Since 2002, when Jared Israel was the first one to point out the lame reaction of the US air defense to the hijackings (not being able to intercept leastwise one of the airliners), there's still no satisfying answer to the question for those who were responsible for the fatal delays.

The 9/11 Commission basically argues that the existing protocol for the collaboration between the FAA and NORAD in the case of a hijacking was "unsuited in every respect" because it was designed for "traditional hijackings" rather than suicide terrorists using hijacked planes as missiles. The Commission Report describes meticulously how the information "Flight X is hijacked" was ought to be processed from the basic FAA controller who spots the plane, upward the FAA hierarchy to the "hijack coordinator" who contacts the NMCC (National Military Command Center), and - after seeking approval from the Secretary of Defense - down the NORAD chain of command.

There is an entire section on this subject ("Interagency collaboration", p. 17/18), which is copied word by word from the Commission's Staff Statement No. 17, a working paper from June 2004, with one remarkable exception. The sentence "Most FAA centers had a civilian employee to coordinate with NORAD, for situations like training exercises", which is written down in the statement, didn't manage it into the final report.

It should have, however. On 9/11, these civilian employees, also known as "military liaisons", were in direct contact to the NEADS air defenders. So the regional FAA Centers were by all means able to shortcut the intricate protocol by simply telling their own military liaison to call up NEADS. And this is exactly what happened:

Flight..................................................11.........175.........77.........93
Controller realizes flight is hijacked.......8:25.......8:55.......----........9:32
Notification of NEADS.........................8:37.......9:03.......----.......10:07
Delay in minutes..................................12...........8..........----.........35

While 8 or 12 minutes look to be a reasonable time for controllers to figure out the situation, discuss various options and get clearance from higher-ranking FAA managers, the outstanding 35 minutes delay for Flight 93 requires a closer look at Cleveland Center, the facility responsible for Flight 93. (Flight 77 is a special case because it was not believed to be hijacked, but missed; it completely vanished from the radar scopes of FAA controllers.)

The "Flight 93 is a hijack with a bomb on board" information needed only two minutes from the basic controller to FAA headquarters:

At 9:32, a third radio transmission came over the frequency: "Keep remaining sitting. We have a bomb on board." The controller understood, but chose to respond: "Calling Cleveland Center, you're unreadable. Say again, slowly." He notified his supervisor, who passed the notice up the chain of command. By 9:34, word of the hijacking had reached FAA headquarters. (911 CR, p. 28)

However: NEADS first received a call about United 93 from the military liaison at Cleveland Center at 10:07. We know his name from transcripts of NEADS radio messages: that was Mr. Dukelin - first name unknown. Dukelin was in direct contact to Stacia Rountree from NEADS, he spoke with her at 9:45 and again at 10:00. At both occasions, he alerted her to Delta 1989 - but not one single word on United 93.

Did Dukelin not know about the hijacking of Flight 93? This can be precluded. He was certainly in contact with the Traffic Management Unit and Ed Wolbers, the operations manager:

They are speaking to the pilot, Dukelin talks to Ed and tells him he is talking to HUNTRESS. Ed says D1989 is not being hijacked, he is landing as a precaution in Cleveland.

So Dukelin, like the Cleveland Center management, was certainly aware of the Flight 93 problem. Maybe he was eagerly waiting for an order from above to inform NEADS:

Cleveland even told the Command Center [at 9:36] it was prepared to contact a nearby military base to make the request. The Command Center told Cleveland that FAA personnel well above them in the chain of command had to make the decision to seek military assistance and were working on the issue. (911 CR, p. 28/29)

But the upper FAA management shied away from requesting the help of NEADS:

At 9:49, 13 minutes after Cleveland Center had asked about getting military help, the Command Center suggested that someone at headquarters should decide whether to request military assistance:

FAA Headquarters: They're pulling Jeff away to go talk about United 93.
Command Center: Uh, do we want to think, uh, about scrambling aircraft?
FAA Headquarters: Oh, God, I don't know.
Command Center: Uh, that's a decision somebody's gonna have to make probably in the next ten minutes.
FAA Headquarters: Uh, ya know everybody just left the room.
(911 CR, p. 29)

Everybody left the room. The Headquarters and the Command Center were tracking Flight 93 as it turned around and headed toward Washington. They got the information that it was hijacked and had a bomb on board. They knew that two airliners had already been used as guided missiles - yet nobody of the leading FAA personnel bothered to follow Cleveland Center's suggestion and tell NEADS (via Dukelin) to scramble fighters. What was going on there?

Additionally, at 9:45 the FAA issued the general grounding order for all aircraft. Who ordered it? The official story has it that it was Ben Sliney, director of the Command Center, but there are also reports that it was Monte Belger, deputy director of the Headquarters - not to forget that Norman Mineta claims the glory for himself. No matter who was it - why did this hero make the risky, unprecedented, precautionary decision to "get all the birds down", but failed to make the acute, urgent, if well-rehearsed and operationally easy decision to alert NEADS about a hijacked airliner on his way to Washington with a bomb on board?

There seems to be only one realistic recourse: Flight 93 was part of a military exercise, probably a hijack simulation, and the exercise plot included a delayed alerting of NEADS. The behavior of Belger, Sliney & co. indicates that they didn't view the plane as a threat, but were told (possibly from the Secret Service who - according to Mike Ruppert - had direct access to FAA data) that it was a "special", i.e. a military exercise flight. The purpose of the delayed alert might have been to test NEADS - to make it more difficult for them to intercept the flight in time.

To substantiate this thesis, I take a look at the function of the so-called military liaisons. I've already mentioned that the 9/11 Commission describes their job as "to coordinate with NORAD, for situations like training exercises". An analysis paper from 2001, examining the structure of Air Traffic Control, confirms that the military liaisons dealt with exercises. Moreover it looks that the exercises were the only job of the liaisons.

Military Coordinator: coordinates paper work and flight data for all military exercises within Boston Center airspace.

This certainly applies to the other FAA Centers as well. Also FAA directive 7610.4K ("Special Military Operations") shows up the central role of the military liaisons for the exercises:

FAA Military Liaison Officers’ Responsibilities

1−6−1. ACTIONS

Liaison officers shall take the following actions in connection with proposed military exercises:

a. Encourage mission planning officers to include assigned airspace requirements in the information disseminated with the request for exercise approval.

b. Recommend the use of planning conferences to mission planning officers for the resolution of problems when it is evident that the exercise requirements will generate sufficient traffic to create untenable air traffic or airspace user situations.c. Provide early notification and information to the affected ARTCCs and CARF on any exercises which are classified under subparagraph b.

So by dropping the "military liaisons" from the final report, the Commission avoided questions about their function. Their function was to coordinate military exercises with civilian air traffic. It was not to assist the FAA in the case of a hijacking. Interestingly, there is an interview with the military liaison of Boston Center, Colin Scoggins (as his alias "Cheap Shot"):

As the military specialist I am responsible for all military procedures between Boston Center and the military units in my airspace, and any visiting military units that participate in any of our Special Use Airspace (SUA).

http://sites.google.com/site/911guide/cs

Q: What can you tell about the military exercises of that day, and if they had any effect whatsoever on the response?

Cheap Shot: I never knew anything about them. Vigilant Guardian is an exercise that we don’t participate at Boston Center. We normally are involved in Fertile Spades, Fertile Angels, and Amalgam Virgo’s. Occasionally we will get involved in large-scale exercises such as a while back Amalgam Warrior, and Global Yankee.

http://sites.google.com/site/911guide/cs3

"Cheap Shot" denies any knowledge of or involvement in the ongoing exercises. This comes as a big surprise, because NORAD was conducting several large-scale exercises, Vigilant Guardian being only one of them. Other exercises, not mentioned by Scoggins, were Global Guardian, Northern Guardian, or Vigilant Warrior. NORAD covers the entire airspace of Boston Center. When Boston Center called NEADS, the air defenders thought it was the begin of Vigilant Guardian. Scoggins' "I never knew" claim would imply that NORAD conducted its exercises in Boston Center airspace without any coordination with civilian air traffic control - bypassing Scoggins, the scheduled coordinator.

This is hard to believe and entails the search for an alternative explanation. Here is one: Scoggins was involved in the exercises, but to admit this fact would have opened the doors for more gnawing questions. Many suspect Scoggins of being a gatekeeper, and the job of a gatekeeper is to absorb dangerous questions. This is exactly what he's doing.

A military liaison was not only assigned to the FAA field facilities, but to the Command Center and the Headquarters, too. There is little information available for the latter. The military liaison at the Command Center was the "Air Traffic Services Cell", consisting of Col. John Czabaranek, Lt. Col. Michael-Anne Cherry and Maj. Kevin Bridges. Mike Williams of 911myths.com speculates that the job of the "cell" on 9/11 was to help with the communication infrastructure (teleconferences etc.):

From this description the cell officers earliest task appears to have been to set up the various teleconferences. They were assisting with communications in general, and there's nothing here to say the officers would take it upon themselves to monitor FAA information and pass it on to NORAD, especially if they believed (like Sliney) NORAD had already been informed. It wasn't their job, and they had other things to do.

Other sources suggest, however, that the task of the Air Traffic Services Cell was to coordinate civilian with military aircraft movement, like their counterparts at the field facilities:

Military Air Traffic Services Cell
–Housed within the System Command Center
–Mission -To coordinate all priority military aircraft movement and airspace issues during times of tension, warfare, natural disasters or civil unrest.
–Warfare Support
–Deployment of forces
–Sensitive, specialized, or classified mission coordination
–Military training exercise support
–Natural or environmental disaster assistance
–Civil exercise collaboration involving military participation

On 9/11, there was no tension, warfare, natural disaster or civil unrest, leaving the "military training exercise support" as the residual task of the "cell". This is confirmed by an article of Aviation Week & Space Technology from December 2001, describing the job of the cell as "refresher training", i.e. conducting exercises:

In a fluke, so was what Herndon calls "the military cell"--the Air Traffic Services Cell, created by the FAA and the Defense Dept. for use when needed to coordinate priority aircraft movement during warfare or emergencies. The Pentagon staffs it only three days per month for refresher training, but Sept. 11 happened to be one of those days.

It is unclear if the Air Traffic Services Cell was in direct contact to the military liaisons at the FAA field facilities, but there is reason to assume that. The cell was able to communicate with other military facilities via SIPRNET, the military's Internet:

The ATSC’s response to the terrorist attacks benefits from the fact that, six weeks earlier, the cell had a secure terminal to access the SIPRNET—the military’s classified version of the Internet—installed, along with other hardware, which significantly enhances the movement of vital information. According to Meenan, because the cell has the SIPRNET terminal, “we could immediately look at NORAD and [Defense Department] plans as they evolved; filter, package, and format them, then walk out to the [FAA] national operations manager—who had control of the entire national airspace system—and give him current visibility into… fighter, tanker, and support aircraft activities. It cut down our response time tremendously.”

http://web.archive.org/web/20020913090602/http://www.aviationnow.com/content/publication/awst/20020610/aw52.htm

The last sentence - "it cut down our response time tremendously" - deserves only scorn and derision, considering the 35-minute delay of alerting NEADS to Flight 93. Instead, SIPRNET seems to have been the central tool to conduct the various exercises. Moreover, it was a valuable tool for "interested circles" to make the exercises a springboard for performing the 9/11 crimes.