October 6, 2004

To:  Robert Benzon, NTSB Investigator In Charge of AA 587

cc:  James Cash, Electronics Engineer - NTSB
      Ted Lopatkiewicz, NTSB
      Tom Haueter, NTSB
      Glen Schulze, Electronics Engineer for U.S.Read
      Captain Rudy Canto, Director, Flight Operations Technical, Airbus Industries
      Philippe Plantin de Hughes, Safety Investigator, Bureau Enquêtes-Accidents (BEA)
      Captain Ray Hayes, A-300 Check Airman, American Airlines
      Jim Wilson, Manager of Flight Safety, Allied Pilots Association (APA)
      Mr. and Mrs. Stan Molin, parents of AA 587 First Officer, Sten Molin

From:  Victor Trombettas, U.S.Read

Re:  The "Try Escape" Transmission and the NTSB Study - "Addendum 1 to Group Chairman’s Sound Spectrum"
        dated Dec. 10, 2003 (pdf available here)

Mr. Benzon:

I recently learned that my late November/early December 2003 e-mail exchange with the NTSB about the "try escape" transmission was followed only nine days later by a "Study" from the NTSB's Cockpit Voice Recorder (CVR) Group Chairman, James Cash.  The NTSB refers to "try escape" as the 9:15:51 A.M. transmission.  This letter will refer to it as "try escape".

The NTSB study concluded the following about the "try escape" transmission:

• the words spoken could not be understood
• the words came from an unknown source
• there was no "un-key" noted on the waveform similar to the previous two AA 587 transmissions
• the background noise in "try escape" was lower than the previous two AA 587 transmissions
• therefore, the NTSB conclusion was that it was unlikely "try escape"originated from AA 587.

As the NTSB understands, this transmission occurs at the exact time of the second alleged wake encounter and approximately seven seconds before the time of tail separation, as established by the NTSB.

FAA not a member of the Study Group
Given that the NTSB study was exploring issues directly related to FAA Air Traffic Control (ATC) communications recorded by them and provided by them, it was unfortunate that the FAA did not participate in the study group. 

U.S.Read had extensive discussions, in 2002 and 2003, with an FAA representative who was directly involved in the AA 587 ATC transmissions.  Many of U.S.Read's findings are based on discussions with the FAA. 

"Try Escape" came from a pilot tuned to the same frequency as AA 587
The FAA stated to U.S.Read that they had conducted an inquiry about "try escape" (not long after the crash) and concluded that it originated from an unidentified aircraft tuned to the same frequency AA 587 was on, and that "try escape" did not originate from any FAA controller position, i.e. it wasn't a land line communication between FAA centers. 

Since the pilot did not identify himself, in what was a hurried transmission, the FAA concluded the aircraft was unidentified.  The NTSB study, however, did not reach that basic conclusion. 

The words spoken are "try escape"
In previous communications with the NTSB we have expressed that it is relatively easy to conclude that the words spoken are "try escape" –– not "nice game" as the FAA had initially concluded.  We can forward these communications to the NTSB again at your request.   Our position is firm –– the words are "try escape".

No "un-key" present in "try escape"
The NTSB brought a couple of pre-judgments to this study which we believe biased its conclusion(s):

(1) if "try escape" was from a pilot it must have the usual "un-key" signature and,
(2) if "try escape" came from AA 587 it would have the same "un-key" signature as other AA 587 transmissions which occurred earlier in the short flight.

Both of the above assume that the "try escape" transmission, if coming from any plane, was a normal transmission, and therefore occurred under normal flight conditions.  That is a false assumption to make given what the NTSB knows about the seven seconds of mayhem on board AA 587 before the "loud bang".  "Try escape" occurs at exactly the same moment as the NTSB believes the First Officer (FO) began his "escape" maneuver on AA 587 –– seven seconds before the "loud bang" (the NTSB's assumed time of tail separation).  NTSB investigators referred to the FO's maneuver at this time as the "escape" maneuver during the Hearings in 2002.  This is a remarkable coincidence that should not be easily dismissed. 

Whoever it was who said "try escape" . . . was very rushed –– as this pilot did not identify himself properly.  One possibility the NTSB did not consider was that the "un-key" signature could be present right at the end of the word "escape" –– without the typical flat line (or brief pause) before the un-key signature.  In other words, during normal transmissions pilots will release their microphone (mic) button within a split second of their last word.  Maybe this time, this pilot released the mic button just a bit earlier.

If AA 587 was, at this point in the timeline, experiencing an electrical disturbance on board, then this transmission is no longer a normal transmission.  Therefore, the lack of the typical un-key signature cannot exclude "try escape" from consideration.  If we followed NTSB logic, we would conclude that this transmission did not come from any airplane since it did not have any apparent un-key signature.  But then we would be at odds with the FAA, who concluded the transmission did come from an airplane. 

Lower background noise
The second of the NTSB's two points for dismissing "try escape" as coming from AA 587 was the lower background noise.  U.S.Read had discussed this issue with the FAA.  The FAA did not feel that the lower background noise excluded "try escape" as a transmission from an aircraft.  The FAA offered that how the pilot had positioned the hot boom mic was also a factor.  The previous two transmissions the NTSB referenced in the study focused on the Captain's transmissions.  The FO was using a different mic that may have picked up the background noise at a lower level.

Second, as we have established and as the NTSB is well aware, U.S.Read identified the First Officer's "Losing Control" transmission which occurred approximately three seconds after the loud bang.  We have proven this by showing that the waveforms from both the FAA tape and CVR have a direct inverse relationship (Figure 1 below) –– in other words, the two waveforms literally fit together like a puzzle.  The reason for this inverse relationship is that AA 587's CVR was not recording (hence the CVR flat line) while the FO's radio was transmitting.  This inverse relationship we identified also proves that the loud bang was transmitted to ATC at 9:15:59, along with one of the Level 3 cockpit warning chimes at 9:16:10.  The NTSB never identified any of these transmissions as coming from AA 587. 

Figure 1 - the black waveform is from the CVR (the First Officer's CVR track) ––
                 the blue waveform from the FAA Departure Control ATC tape.
                 Note the direct, inverse, relationship.  This is proof that "losing control" came from AA 587.

This is relevant to our current discussion for a number of reasons but specifically, it addresses the issue of lower background noise.  The "losing control" transmission has similar gaps in the waveform –– in the middle of the word "control", for example –– as with the low noise level (or gap) in the word "escape".  This "losing control" transmission, like "try escape", was not a typical transmission by any means.  The background noise, if any, is not similar to the previous transmissions the NTSB referenced.  Yet we know beyond any shadow of doubt that this came from AA 587, specifically –– from the FO.

Similarities between "losing control" and "try escape" –– and proof "try escape" was not a normal transmission
The "losing control" transmission by the FO also created some "noises" on the Local Control frequency –– at the same time as it was being heard on the Departure Control frequency.

Similarly, as "try escape" was being received at the FAA's Departure Control facility, the first word of that transmission, "try", was being received back at the FAA Local Control facility.  When U.S.Read made the FAA aware of this –– the specialist's reaction was that there was likely a "short circuit or harmonics problem with the transmitting aircraft"

Obviously, the conditions under which "try escape" were transmitted were far from normal and therefore the transmission cannot be investigated as a normal transmission, with normal characteristics.

Since we have proven beyond any doubt that the latter transmission ("losing control") came from AA 587 –– then "try escape", given it's similar behavior to "losing control", is in all likelihood also from AA 587. 

Yet another similarity between the two transmissions is that they both were not recorded by the CVR.  To understand the significance of this –– it's important to understand the timeline.  The NTSB believes that at the time of the "losing control" transmission, the tail and engines had already departed.  Therefore, the NTSB's position is that the absence of "losing control" on the CVR is not an unusual occurrence given the electrical mayhem on board after the loss of the tail and engines.  Herein lies the major dilemma the NTSB must face with the "try escape" transmission.  The NTSB's timeline indicates that "try escape" occurred several seconds before tail and engine separations –– several seconds before any electrical mayhem on board.  Yet "try escape", and it's abnormal and similar behavior to "losing control", says quite the opposite –– that electrical mayhem had already been let loose on board AA 587 before tail and engine separations. 

This is why "try escape" is powerful evidence of a significant event on board AA 587 before the tail separated.  And one of several reasons why U.S.Read has not been able to ignore the many witnesses who saw a fire or explosion before the tail departed. 

The NTSB's conclusions about "try escape" lead to a remarkable set of coincidences
If we follow the NTSB's logic, we end up with the following remarkable set of coincidences:

• some other pilot, tuned to the same frequency as AA 587, said "try escape" at the exact same moment as the NTSB believes the FO of AA 587 began executing the American Airlines "escape" maneuver.
• this "other" pilot who said "try escape", sounds very much like the FO, Sten Molin, to those that knew him best, beginning with his family.  This is further corroborated by friends and fellow pilots who also knew Sten Molin well.  A sound spectrum analysis by Glen Schulze has also shown similarities between the "try escape" voice and Sten Molin's voice as found on his home answering machine (Figure 2 below). 
at the same moment that Sten Molin was initiating the escape maneuver on AA 587 –– the "other" pilot, who sounded like Sten Molin and happened to use a word describing a maneuver Sten Molin was performing on board AA 587, just happened to have a short circuit problem with his radio. 

U.S.Read believes that the NTSB needs to reconsider their conclusions.  Our conclusion, since February 2002, has been that "try escape" came from AA 587, and that this transmission is a tremendous clue into the nature of what the crew of AA 587 was faced with.  

A few comments from people very close to FO Sten Molin:
Sten Molin's father (a retired Captain who is still a flight instructor): stated to U.S.Read, "I have no doubt that it is Sten's voice.  I was shocked to hear his voice when I thought the comment [before listening to it] was attributed to Captain Ed States.  The expression is "try  escape?"  I have no doubt that it is a question to Captain Ed  States.  The end of the "escape" is raised intonation. I only lived with that voice for 34 and a half years. I could be wrong, but as of now, "I have NO doubts as to the person or the words."
 A friend of the Molin family, a Police Lieutenant and Pilot, who knew Sten Molin for 20 years, said it was Sten's voice and the words were "try escape".

Figure 2 - Sten Molin's voice compared with the "try escape" voice.  The frequency content is similar.

Sten Molin's voice compared with the "try escape" voice
This sound file (a wav file), highlights the strong similarity between the real voice of Sten Molin (from off his home answering machine saying, "you've reached 8 - 6 - 9") with the voice saying "escape" from the FAA tape. 

The missed clues from the CVR
The most significant clues about  "try escape", and the nature of the initiating event the crew was battling, are on the CVR and the Sound Spectrum Study the NTSB performed.  Sound Spectrum Chart 6 (Figure 3 below) from the NTSB's CVR Factual Report shows more than one apparent discontinuity –– dramatic shifts in the spectrum that the NTSB attributes to the parameters of the study, but that some experts believe could very likely be indicators of stops/starts of the CVR resulting from electrical disruptions.  This would certainly explain why Sten Molin's "try escape" was not recorded on the CVR.  U.S.Read has added timeline annotations to Figure 3 below. 

Figure 3 - Sound Spectrum Study during Pilot's escape maneuver showing dynamic events on the CVR

What is most interesting is that the first spike of noise energy (or discontinuity) occurs at the same moment as the "try escape" transmission, at 9:15:51.4.  Another remarkable coincidence –– considering the NTSB's position. 

Our position is that these are all clues to the true cause of the crash of AA 587.  Clues that have been overlooked by the NTSB investigation. 

What caused the corrupted, abnormal transmissions from AA 587?  Why did the CVR experience stop/starts several seconds before the tail separated?  How does the NTSB explain the dynamic events as displayed in Chart 6 from their Sound Spectrum Study? 

These are the questions the NTSB has left unanswered by passing quick judgment on "try escape". 

Victor Trombettas