November 4, 2003 - by Victor
As we approach the 2nd anniversary of the 2nd worst aviation crash in U.S. history, U.S.Read and the dozens of experts who have contributed to our Flight 587 coverage extend our heartfelt sympathy to the families of the victims. U.S.Read also feels a sense of sorrow because we are convinced the truth of Flight 587 will never be revealed. We have lost faith in the NTSB and any possible Governmental oversight. The one arena we felt might still hold some hope for the unveiling of this mystery -- the lawsuits by the families -- will also fail to deliver the most precious settlement -- the truth. U.S.Read does not believe that the tail departing the aircraft was the cause of the crash. Tail departure was no more the cause than the engine separations were. Both tail and engine departures were a consequence of some catastrophic event which led to a loss of control of the aircraft and the subsequent in-flight breakup.
The day of the crash, Chairman Blakey's comment that "all indications are that this is an accident" clearly showed the U.S. Government's bias. We believe that this bias, this rush to judgment, guided the NTSB down the wrong investigative path that saw them ignore the witnesses and at times discredit them. They have also misinterpreted the flight recorders and most of the other evidence. This will all culminate in a probable cause that will not accurately represent what happened that awful morning two years ago.
In the year since the Hearings and the release of the factual reports, U.S.Read's experts have seen many indicators of a flawed investigation. Quite frankly, we are overwhelmed by it and do not know where to begin in our coverage. Perhaps the first thing we can say about the official investigation is that if we accept what the NTSB is telling us, then we have more reason than ever to believe that today's jetliners are terribly unsafe and the NTSB and FAA have done nothing to change that.
What They Believe
Picture 1 at 9:15:53.2 - Load Limits Exceeded
Picture 1 shows Flight 587 at 9:15:53.2 (approximately 5.3 seconds before the NTSB believes the tail departed). At this moment the aircraft was in only a 5 degree nose-right sideslip (the nose was to the right of the direction of flight) and the rudder was deflected to the left 11 degrees (the 2nd of 5 rudder movements -- a.k.a, the first "reversal" of the rudder). It is important to note that in the 3 pictures that follow, the aircraft is never in what the industry calls an "upset". The blue and brown colored circular ball is the artificial horizon indicator which shows bank (roll) angle and the position of the nose with respect to the horizon (pitch). For example, in Picture 1, the aircraft is in a 9 degree climb and has a 10 degree left bank. The NTSB states the FAA's tail limit loads (as defined by the FAA certification requirement) were slightly exceeded at this moment. Simply by depressing the rudder pedal just a couple of inches in both directions in less than 2 seconds, the pilot has placed loads on the tail beyond those the FAA felt should ever be experienced in service.
Picture 2 at 9:15:56.8 - Ultimate Load Exceeded
Picture 2 shows the aircraft at 9:15:56.8 with a 7 degree nose-right sideslip and the rudder deflected 10.2 degrees left (the aircraft is almost completely level -- no noticeable pitch or roll angles). We are told that now the tail's "ultimate load" has been slightly exceeded. The "ultimate load" is the limit load multiplied by a safety factor of 1.5. The tail must survive this load factor for 3 seconds according to the FAA requirement.
Picture 3 at 9:15:58.5 - Limit Load exceeded by factor of 1.9 times
Lastly, Picture 3 shows the aircraft at 9:15:58.5 (when the NTSB believes the tail departed) with a 10 degree nose-left sideslip and the rudder deflected 11.5 degrees right (the nose is pitched down only 3 degrees and there is an 8 degree bank to the right). At this instant, the tail is suffering a load 1.9 times the limit load and has performed as well as even a new tail could be expected to perform. Just look at the aircraft in Picture 3 and understand that the NTSB is telling us that (a) In this type of attitude (this is still not an upset by industry standards) the pilot had better not apply any rudder in the opposite direction of the sideslip (or yaw), and (b) the imposed stress on the tail is way beyond what it was ever designed to endure.
What if an aircraft gets into a sideslip because one engine has quit at some speed above 270 knots? How much rudder can a pilot use to compensate for the sideslip that will ensue without exceeding load limits? Half the available distance? That would mean the pilot could only move his foot about a half inch (depending on the aircraft model) -- since a little more than an inch would throw the rudder to its full travel distance. Worse yet -- what if an unintended sideslip ensues and the aircraft suffers an uncommanded rudder movement to the opposite side? Then what? Flight 587 supposedly went from zero load on the tail (during the last rudder movement in Picture 3) to beyond ultimate load in only four tenths of a second. By no means enough time for a pilot to somehow respond and prevent a catastrophe from occurring if the rudder moves on its own.
We Do Not Believe
Of course, history tells us that this just can't be true. If tails were really constructed with such low tolerances for stress, surely, more tails would have fallen from jetliners long before Flight 587. But what matters here is that the NTSB believes this. Both the NTSB and the FAA have done nothing about this very disturbing situation except to tell the airlines to make the pilots aware of this new understanding, and warn pilots not to reverse the rudder. U.S.Read's position is, as members of the flying public, that if the NTSB and FAA really believe this, then increasing the certification requirement appears to be an absolute necessity. This has not been done. We see no indications that anything sensible will be done. All they have done is put the pressure on pilots to be aware of how sensitive the rudder system is and how easily a tail can break off.
Ultimately, U.S.Read does not believe that tail separation was the cause of the crash. The very evidence the NTSB has presented to establish the load calculations and rudder movements mentioned above are unsupported by the Flight Data Recorder. That is just the tip of the iceberg. The evidence does suggest that at the time of Picture 3, something catastrophic had already occurred to Flight 587. The tail very likely was still attached beyond this point and departed up to 8 seconds later. If the flight data recorder, the cockpit voice recorder, the radar data, the tollbooth video, the debris field, the Air Traffic Control tapes, the eyewitnesses, were all correctly interpreted, without the NTSB's bias, the initiating event before the assumed tail separation point would be clearly identified. U.S.Read hopes to cover all this in more detail in upcoming articles.
Our warmest thoughts and prayers are with the families.
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