My goal in telling this story has always been to tell it in a compelling and unbiased manner. That’s why the book relies so heavily on the comments and writings of some of the very people who were there at the time. If what I write comes across as biased, it’s only because I find the evidence so overwhelmingly against the NTSB findings. So when Dave Haase, one of the members of the TWA accident investigative team working on TWA 841, wanted to share his thoughts about the investigation, I was more than happy to give him this forum. You can also hear and see a portion of the interview I did with Dave in the post overlooked clues. One last thing before I hand it over to Dave, I had an opportunity to work with a very talented 3D animator, Mike James of mikejamesmedia.com who provided a number of images I plan to use in the book. The image in this post is one of the great images he provided.
Dave Haase Former TWA accident investigator
I was privileged to be a member of the TWA ALPA accident investigation team in the case of TWA 841 and worked with Jim McIntyre, the then chairman of the TWA ALPA accident investigation committee, as well as with Dale Bebee a TWA pilot representing TWA flight operations management. We were assisted by ALPA’s then Director of Accident Investigation, Harold Marthinsen. Subsequent work by Leigh Johnson, among others, shed additional light on a number of important technical aspects.
My work was primarily on the technical side of flight data recorder analysis. The recorder on the aircraft involved, a Boeing 727-100 series, used an earlier recorder, a foil tape unit that did not have the capability to record the aircraft’s pitch or roll attitudes. However, using equations of motion for a vertical gyro and available recorder data (namely time, altitude, heading, vertical acceleration and airspeed), it was possible to derive pitch and roll attitudes.
Preliminary data analysis submitted to the NTSB by the manufacturer showed roll attitudes that did not match the flight crew’s recollection. But, based on some of the work we did, our analysis generated different results. We presented our findings to a staff engineer at the NTSB for his review. After examining the information, he concluded the preliminary analysis was incorrect and what we had submitted was valid. The interesting point is that this new analysis showed roll attitudes that corresponded with flight crew’s and particularly Capt. Gibson’s recollection of events. Throughout the investigation I never came across any information that contradicted Hoot’s testimony.
Of all the investigations that the Board had conducted, the formal 841 NTSB investigation was one of the most significant in the Board’s history and one of the longest, lasting more than two years. Over that time I met with Hoot and others numerous times and he was the same person in business meetings as he was in informal settings such as when we went out to dinner.
After the investigation was completed by the NTSB it was then time for the five member board to make a judgment based on the report put together by NTSB staff and to vote on “the probable cause.” Of some interest, only three of the five members were present at the Board meeting. Of those three Board members, I found the statements of member Francis McAdams of particular interest because he dissented, in part, on the probable cause statement. I have copied that statement from the formal NTSB report and it is shown below.
FRANCIS H. McADAMS, Member, filed the following concurring and dissenting
statement:
Although I voted to approve the Board’s report which concluded that the extension of the leading edge slat was due to flight crew action, I do so reluctantly. The report as written, based on the available evidence, i.e., the analysis of the flight data recorder, the simulator tests, .the flight tests, and the tilt table tests, appears to support the Board’s conclusion. However, I am troubled by the fact that the Board has categorically rejected the crew’s sworn testimony without the crew having had the opportunity to be confronted with all of the evidence upon which the Board was basing its findings. At the time of the first deposition, the following evidence was not available to the crew or to the Board: the flight data recorder analysis, the results of the simulator and flight tests, and the tilt table tests. Although the crew was deposed a second time, their testimony was limited to one issue, i.e., the physical location of the flight engineer at the time of the incident. I had recommended that since the Board was ordering a second deposition it be conducted denovo so that the crew would have been aware of all the evidence. The Board did not agree.
Furthermore, I do not agree that a probable cause of this accident, as stated by the Board, was “the captain’s untimely flight control inputs to counter the roll resulting from the slat asymmetry.” In my opinion, the captain acted expeditiously and reasonably in attempting to correct for the severe right roll condition induced by the extended slat.
At the least, I was disappointed by the Board’s handling of the accident. But, I was thankful that McAdams spoke up, argued on behalf of the crew and provided his dissenting opinion. And, I firmly believe that Hoot saved the day in difficult circumstances.
It should be noted that, after appropriate review, TWA fully reinstated Capt. Gibson to normal flight status and he subsequently qualified on the L-1011.
About three months ago, Hoot and I talked on the phone for at least half and hour. We had a great discussion of times past, and as was typical for him, he was most generous and gracious with his thanks. He will not be forgotten.
I just watched the Air Crash Investigation episode dedicated to TWA 841. I am absolutely outraged at the obvious cover up of a defective plane that was blamed on the pilots. This is a disgusting example of big business covering their a$$. These men should have been hailed as heroes for saving the souls of everyone on board. I wish I could contact the pilots or their families to express my support of them. If by chance this message could be passed along, please let them know that the fact that they were unjustly accused and used them as the scapegoats of the Boeing, TWA and the NTSB is appalling and revolting. I was also surprised at how their fellow pilots and other crews treated them, shame on those people.
Sending my warmest regards and utmost respect,
Amy Thomas
Houston, TX
I was a passenger on TWA 841. I have followed the story and reports over the years. I am thankful for my second chance at life and thank the pilots and crew for that second chance. I am now a dean of engineering and tell the story (filled with engineering) of that life changing experience with students and others. Thank you Hoot!
the FAA covers up for the aircraft manufactures as they did when the vertical stabilizer came off the JF Kennedy flight in NY. I spoke to the father of the pilot who told me that test pilots could hardly stay withing the limits of the rudder specifications.. A similar thing happened to the air france out of brazill where the tail was found intact miles and miles from the plane.. they should have designed it for the actual rudder failure prior to the stabilizer failure. One rudded did come off either going to or leaving cuba.
the FAA covers up for the aircraft manufactures as they did when the vertical stabilizer came off the JF Kennedy flight in NY. I spoke to the father of the pilot who told me that test pilots could hardly stay withing the limits of the rudder specifications.. A similar thing happened to the air france out of brazill where the tail was found intact miles and miles from the plane.. they should have designed it for the actual rudder failure prior to the stabilizer failure. One rudded did come off either going to or leaving cuba.I have to wonder if they exceeded the the Mach number of the plane at 39,000
With respect, there was no cover-up regarding AA587. Yes, the configuration of the rudder pedals had the effect of making them unusually “sensitive” to large inputs compared with other types – and yes, the use of composite materials in the structure meant that the failure mode could possibly have been more sudden. But neither of those factors can be used to dispute the hard evidence that the vertical stabiliser attachment failed due to the aerodynamic load on the structure exceeding the ultimate design limit.
The fundamental problem was that AA’s advanced handling “AAMP” course – attended by the AA587 PF – was flawed to the point of being outright dangerous when it came to how it taught wake turbulence upset identification and recovery. The focus seems to have been based on the loss of Delta 9570 (A DC-9 following a DC-10), and the simulator exercise implied that a wake turbulence encounter could cause a sudden roll to a bank angle of 90 degrees, from which the students had to recover. The fact that an upset that severe represented a theoretical worst-case scenario which had never been encountered in reality was apparently not communicated to the students, nor was the fact that larger wide-body types are considerably less prone to flight path upset due to their greater mass. The unfortunate F/O of AA587 was therefore left with (and apparently deeply affected by) the erroneous impression that any wake turbulence encounter could potentially result in an extreme upset scenario which could only be recovered via the use of full rudder input – to the extent that he was written up several times as having used excessive rudder input when it was not required (but no attempt seems to have been made to find out why). In layman’s terms, that part of the AAMP course had the opposite of its intended effect; in that rather than giving this pilot extra confidence, it left him scared witless of wake turbulence encounters. He had been taught to use rudder to recover from an extreme upset, but it seems that in his mind he needed to use the rudder for any wake turbulence encounter, even before a significant upset happened. Applying the force to the rudder pedals (repeatedly, and in opposite directions) as he did would have caused failure of the vertical stabiliser in any similar type.
As far as AF447 goes, the failure analysis of that vertical stabiliser proved conclusively that it separated on impact with the ocean – the distance from the rest of the wreckage (when it was eventually located a year or so later) was a result of the drift caused by the ocean currents.
I approved your comment, however, the accident you mentioned is not referenced at all in my book about TWA 841.
Hi Emilio,
Thank you for approving the comment, despite it not referencing TWA 841 – for the record, I was referring to the accidents mentioned in the previous post by Joseph R DuPont. And I did so because, while it’s absolutely the case that the regulators (and sometimes the investigative boards) have possibly been swayed by manufacturer input in the past, that wasn’t the case for those accidents. For better or worse, something that hasn’t changed a great deal from the days of TWA 841 to AA587 and AF447 is the amount of rumour accidents generate, and the potential effect such rumours may have on the piloting community and the general public.
Also for the record, I bought a Kindle copy of “Scapegoat” the evening I found your site, read it cover-to-cover over two nights, and I was very impressed by both the quality of the writing and the research. I’ve had a few thoughts, and if you’ll forgive the presumption (and are willing to humour me) I’ll send along an email soon.
I also was a passenger on flight 841. I was on a business trip and the incident had a significant impact on my life. Immediately after returning to work I informed upper management that they would have to find someone else to do the flying. I also refused to fly at all for a year or longer. When I finally relented and started flying again it was mainly for personal reasons. It was 21 years later that I had a flight with the # 841, although it was uneventful, I still do not like that number or any other flight number that adds up to 13. To me Hoot was a hero, my wife agrees. I wish I could have met him in person.
When I read about this flight (841) and saw the Special about the flight, I was flabbergasted to understand that the NTSB came to the conclusion they did. I also found it hard to believe that Boeing was actually allowed to lead the Investigation into the disaster. I love to watch shows about air disasters, and ensuing NTSB investigations of those disasters, yet I found myself surprised with the obvious investigation failures from the NTSB. This WAS a clear case of cover-up. I suggest anyone who believes the findings of the NTSB, Boeing, or TWA, regarding this event, should watch Apollo 13, or at least read the book Lost Moon by Captain Jim Lovell, he (Jim Lovell) was also told that what had happened to their Spaceship was “Impossible”; or perhaps those same people can read up on Rudder Hard-Over! I hail the heroes, being the pilots and crew, of Flight 841 for saving all the lives on board.