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Remarks before Employees of NASA Langley Research Center & Air Combat Command Employees, Hampton, Virginia
Jim Hall
NASA Langley Research Center & Air Combat Command Employees, Hampton, Virginia

Good morning and thank you for inviting me to speak to you today. I am especially honored to appear before this group of distinguished National Aeronautics and Space Administration employees. The Safety Board and NASA have been working hand in hand over the years to improve aviation safety in a variety of ways.

Before I begin, I am sure you are aware that the Safety Board is currently investigating a general aviation accident that occurred here a couple of months ago. One of the pilots killed in the accident, Susan Adkins, was a librarian here at the Langley Research Center. To those of you who knew her, or know members of her family, please accept my sincere sympathy. Our investigators are working on the factual report of this tragedy, which should be published by the end of the summer. A summary of that factual will be placed on our web page, which currently has a preliminary report on the accident. It can be found at

There is nothing anyone can say or do to mitigate the loss of Ms. Adkins to her friends and family, but we hope the results of our investigation will help reduce the possibility of similar accidents in the future.

When I became Chairman of the National Transportation Safety Board about 4 years ago, I of course had no inkling about the level of activity my agency was about to enter. July 1994 saw the end of an unprecedented 27-month period in which the major U.S. scheduled airlines incurred no passenger fatalities: a billion passengers carried safety to their destinations.

The USAir accident in Charlotte, North Carolina changed all that. It was closely followed by another USAir crash near Pittsburgh; and then crashes involving American Eagle in Roselawn, Indiana; another American Eagle near Raleigh-Durham; American Airlines in Colombia; ValuJet in the Everglades; Delta Air Lines in Pensacola; TWA flight 800; United Express in Quincy, Illinois; Comair in Michigan; and Korean Air in Guam. And, we’ve also lost two FedEx widebody planes and had another major cargo accident in Miami.

That doesn’t count the Birgen Air and Aeroperu crashes that required our involvement in arranging deep-water searches for flight recorders, and assisting those countries’ investigations. And, it doesn’t include Silk Air in Indonesia, and a recent 737 crash in Colombia, after both of which we assisted the foreign government’s investigation. One day, a few weeks ago, we had representatives of 5 different countries working with our laboratory on various investigations.

In times past, the Board, with a few pilots and a few engineers, could determine the probable cause of just about any airplane accident that came along – at least to the level necessary to promulgate coherent, viable recommendations to the regulators and to industry. These recommendations are really the essence of the Safety Board’s work. The best accident investigation in the world is simply an academic exercise if no changes come about because of the investigation. Nowadays, however, airplane control systems, airplane navigation systems, and air traffic control systems have become more complicated – I guess most of that complication was developed right here – than they were even a few decades ago in the era of the Boeing 707s and Douglas DC-8s.

Additionally, although the rate of accidents has declined, the number of commercial airliners that are flying at any given time is increasing at a fast pace. I am sure you have heard the ominous prediction that by the end of the first decade of the 21st century, we could be faced with a commercial airliner hull loss every week, if the rate of accidents remains the same as it is today.

It is important to also realize that the Safety Board is simply not a research organization. We try to be the best in the world at what we do – that is, investigate aircraft accidents – however, we are not a research facility. Our 125 or so investigators and scientists are necessarily and by charter, a reactive group. We react when an airline tragedy occurs; it is not our mission to conduct or fund basic research. That mission has been given to you and the FAA.

This then, is the challenge we are faced with today, providing the highest level of service to the American people while maintaining a fairly modest expenditure. In fact, it costs each citizen just 18 cents a year to fund the National Transportation Safety Board and all it does, less than it costs to mail a postcard.

This is one of the reasons we need a second set of eyes, in the form of very specialized, research-oriented expertise. In fact, it is becoming a routine part of the aircraft accident investigation efforts of the NTSB. It is something that gives us more leverage to accomplish our goal. Like you, we are funded by the American people. They should get the benefit of all of our expertise, as well as the expertise of major scientific and research organizations, in the investigations of aircraft accidents. But we require this expertise for more than economic efficiencies. Today, we find ourselves under increased scrutiny for a number of reasons – not the least of which are, 1) the public’s concerns regarding government credibility, and, 2) the litigious nature of our society.

Our ongoing investigation into the loss of Trans World Airlines flight 800, almost two years ago, illustrates how the Safety Board has called upon research groups within organizations like NASA and the Air Force to attempt to prevent a similar tragedy.

TWA 800 is arguably the most complex, and most expensive, investigation the Safety Board has ever entered into. Within a short period of time after the U.S. Navy began bringing up pieces of the airplane for us to examine, it became apparent that fuel vapors within the center wing fuel tank of the airplane had ignited, and the ensuing explosion broke the airplane apart at about 14,000 feet. The issue of foul play was explored intensely by us and the FBI for over a year, and neither agency found any evidence to indicate that a criminal act brought the plane down. Our main focus of investigation has become the specific mechanism within the center wing tank that caused the explosion. We quickly discovered that although a general understanding of fuel-air explosions within airplane fuel tanks had evolved over the years, a true, complete understanding of the nature of such events did not exist. Even the understanding of the chemistry of jet fuel was woefully incomplete.

It soon became apparent that little work had been done regarding a number of issues surrounding our investigation. And what work had been done was out of date. As a result, the Safety Board called upon several research organizations around the world for assistance. The response to our requests for help has been enormously gratifying. Let me give you just some examples of the work underway.

An important program of research was launched at the California Institute of Technology under the direction of Professor Joe Shepherd to measure the flammability characteristics of "Jet A" fuel and to determine the minimum energy required to trigger an explosion in the center wing tank.

We also needed to determine what the temperature and fuel-air concentration ranges within a Boeing 747 center wing tank are during the takeoff and initial climbout phase of a flight. At no small expense to the taxpayers, we leased a 747, and prevailed upon researchers at the University of Nevada at Reno to devise a gas sampling apparatus to place in the airplane, and later to analyze the fuel-air ratios similar to those that existed at the time of the accident. This information, and the temperature and vibration data derived from the series of nine test flights proved invaluable and provided us with an excellent baseline for further research.

Researchers at Cal. Tech and Applied Research Associates also performed a series of quarter-scale explosion tests for the Board at a facility near Denver, Colorado. We are hopeful that the results of these tests will help us determine the location of the ignition in the TWA 800 fuel tank.

Computer modeling efforts by researchers at Sandia National Laboratories in Albuquerque, New Mexico; Christian Michealson Research Institute in Bergen, Norway; and Combustion Dynamics Limited in Nova Scotia are also underway to better understand the explosion in the center wing tank and the damage it caused to the airplane.

Our work with scientists with the Air Force's Propellant, Oil, Fuel, and Lubrication Laboratory and the Electronics MLSA Laboratory have increased our understanding of potential sources of ignition in the fuel tank.

Our investigative efforts have also included a great deal of work with NASA researchers. Our investigators have worked with your scientists to examine fuel pumps and fuel probes to help determine the possible sources of sparking that may have ignited the fumes within the center wing tank. Other work at the Marshall Space Flight Center involved the examination of rubber 0-rings associated with fuel tubing connections within the tank, and center wing-to-cockpit wiring associated with the fuel quantity indicating system in the airplane.

Some of NASA’s work, however, had unintended consequences. The Kennedy Space Center and the Wallops Flight Facility, during the early part of the TWA investigation, launched missiles, as they routinely do. After all, that’s part of their job. Unfortunately, one of the theories under active consideration at that time was that a missile had shot down TWA 800. Several airline flightcrews spotted the contrails of the test missiles from about a hundred miles away, and were concerned that these missiles were aimed straight at them.

Not all of our research focused on the center fuel tank systems. Brookhaven National Laboratory assisted our metallurgists as we systematically examined recovered airplane components for evidence of high-speed penetrations. Sandia National Laboratory and the Naval Weapons Center at China Lake also helped determine whether TWA 800 was struck by a missile.

The University of Pittsburgh was tasked with figuring out the mathematical probability of a meteorite striking an airplane over the United States at any given time. Its researchers found that the probability was once every 59,000 to 77,000 years. You may laugh, but letters to the Safety Board about meteorites effectively stopped after the topic was discussed at our public hearing on TWA 800 last December.

All told, there have been nearly 20 research facilities assisting us in this investigation.

I have highlighted the TWA investigation because it is our most extensive endeavor involving the research community. However, other ongoing airplane accident investigations are also benefiting from similar cooperative efforts:

• Our examination of the hydromechanical aspects of the Boeing 737 accident near Pittsburgh several years ago has been aided by a panel of experts from both industry and academia.

• Our investigation into the loss of an ATR-72 due to wing icing in Indiana was successful, in part, because of the work of NASA Lewis.

• NASA Lewis is also helping us in our investigation of the Comair EMB-120 crash in Monroe County, Michigan last year.

• Finally, your studies here at NASA Langley on runway friction have helped us understand the mechanisms of several landing and takeoff overrun accidents.

I would be remiss if I did not mention other research efforts underway at NASA that, if successful, will go a long way in mitigating the results, if true, of those predictions about the marked increase in the number of accidents in future decades because of the projected growth in airline traffic.

I was a Member of the White House Commission on Aviation Safety and Security. It was one of the most fulfilling tasks I’ve ever had in government, because it brought together representatives of government, industry and the general public and resulted in about 50 recommendations aimed at such diverse subjects as research and development, airport security and the treatment of victims and their families after accidents. On of the recommendations of that Commission was:

Government and industry should establish a national goal to reduce the aviation fatal accident rate by a factor of five within 10 years and conduct safety research to support that goal.

There is no doubt that NASA, including many of you in this room today, will have to be a major part of that effort if that lofty goal is to be reached. I have spent the morning with Mike Lewis, Program Manager of this project, and I am impressed with your early efforts.

However, until that day, we must continue our work. And the efforts I’ve described for you shows how far we’ve come from the days of just "kicking tin." To retain our credibility, we can no longer just rely on our traditional sources of support. We must be innovative and search out the best available.

Thomas Jefferson said, "The care of human life and happiness is the first and only legitimate object of good government." That is what the Safety Board does every day, and it is what all of you do in your roles at NASA or the Air Force or other government agencies. You can be proud of the work you do for the American taxpayer, and we can all be proud of the work we have done together to help ensure the safety of those we serve.

Thank you for inviting me.


Jim Hall's Speeches