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