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Crash Site Secrets

Christine Negroni

Christine Negroni is an aviation writer, investigator, and journalist whose work appears in THE NEW YORK TIMES. She has worked as a television correspondent with CBS News, CNN, and various local television stations. Her book, DEADLY DEPARTURE on the crash of TWA Flight 800, was a New York Times Notable Book in 2000. Ms. Negroni sits on the FAA's Aging Transport Systems Rulemaking Advisory Committee, representing the National Air Disaster Alliance. She lectures on aviation and air safety to schools and organizations and is interviewed frequently on American and British television. Ms. Negroni lives in Connecticut with her husband and four children.

Is there anything to the lingering theory about a missile attack on TWA Flight 800? There are a lot of people who seem unconvinced by the official explanation for the crash (that the explosion was ignited by an excess of fuel vapor in the plane's fuel tank).

If anything lingers about the theory that a missile brought down TWA Flight 800, it is that a missile could have brought down the airplane, and that while it did not in the case of TWA 800, missiles are a serious threat to commercial aviation, a threat that needs to be addressed. In small part, it has been through the FAA's actions recommending that airplane manufacturers reexamine their theories about fuel tank flammability and make changes to reduce the amount of time the airplane's center fuel tank is in a volatile state. Should an airliner be a target of a missile attack, eliminating the volatility of the tank would reduce the likelihood of an explosion in the center tank, that's why some military aircraft already have fuel tank inerting systems onboard.

Had TWA Flight 800 not exploded so mysteriously back in 1996, had the real cause not been so difficult to pinpoint, I do not believe this important improvement in air safety would have come about.

As I reported in my book, DEADLY DEPARTURE, the eyewitnesses to the explosion of TWA flight 800 on July 17, 1996 saw a stream of light in the sky ascending, followed shortly by a large explosion. The initial conclusion was that this was a missile hitting the plane. What's come to light subsequently however is that this stream of light was the airliner itself ascending after the first explosion triggered by a spark in the fuel tank knocked off the front section of the plane. When the plane rose some 2,000 to 3,000 feet there was a second ignition, this time of the atomized fuel spinning out of the ruptured wing tanks. The second explosion was followed by a "curtain of fire" which was the falling, burning fuel so many eyewitnesses reported seeing.

In the post-September 11 world, it is easy to believe that a missile brought down the airplane. But not a single piece of wreckage shows signs of inward ignition of the fuel tank where the explosion originated. Further, months of sweeping the ocean floor turned up not a shred of a missile.

One needs only look back in history to realize that fuel tanks on commercial and military airplanes had been exploding with a frequency of about one every four years to find that a design flaw was the true culprit in the disaster.

If, as was pointed out in the "Crash Site Secrets" episode regarding aviation improvements, innovation and the introduction of it are often a function of a cost/benefit analysis ... how much within the world of innovation is held back as a function of cost? Shouldn't true innovation be defined as an unmet need that no price is too high for?

Sometimes, an airline disaster investigation will point out a previously unknown need, providing to inventors an incentive to create something that will pay off later. But there is an immense world of inventions, gadgets, testing apparatus and design innovations, an unknowable but probably large percent of which will never see the light of day. Of course, there are exceptions. Let's not forget the Wright brothers, who worked long and hard with only the proceeds from their bicycle shop to create a controllable airplane. Even so, it was years before Orville and Wilbur Wright started making money on their innovation.

I live next to an American international airport. How can technology keep my community safe from health, safety, and social problems generated by the airport? The issues deal with noise, air quality, concerns with terrorism, and aircraft accidents into our community homes.

In the near future, a few of the problems that were once considered a given for airport communities will diminish and I am referring to noise, air quality, and the threat of air crashes into proximate communities. The solutions are the result of ever more sophisticated flight management systems (FMS) which can control take off, navigation, fuel flow, and landing more precisely than humans. The computerized systems are constantly analyzing and re-adjusting for more accurate navigation, including for those portions of the flights designated around airport area quiet zones. FMS also enable pilots to land the aircraft safely in low visibility conditions. Already, innovations in engine design make for quieter engines, more fuel efficiency, and less air pollution.

On the "Crash Site Secrets" program, there was discussion about a new material for baggage containers. This container used a composite or layered material and it was able to contain the force of a bomb blast. Do you have any additional information on the manufacturer, other applications, or the status of patents?

Blast containing baggage receptacles have been under study by the FAA for quite a while, the initial push following (by several years to the frustration of the families) the in-flight bombing of Pan Am 103 in 1988. The issues revolve around 1) Weight -- which is about 1/3 greater on the hardened containers, 2) Price -- hardened containers could be ten times the cost of an aluminum one, 3) Logistics -- how will new containers work in the baggage loading process? How many are needed per airplane? How interchangeable will the containers be from aircraft model to model? Various materials have been tested including fiberglass laminates and Kevlar and the FAA has determined that the idea is workable, but progress on this issue is slow.

More information about the companies working on the development of hardened baggage containers is available at the TSA website,

Will either the new Airbus A380 or Boeing's 7E7 Dreamliner fly at a higher altitude than normal to create less turbulence, especially if they're going to add a children's play area, a gym, a bar, shops, and a mini casino? And isn't that a bit extreme to be adding for comfort?

Don't pack your workout shoes just yet. Turbulence, as you've pointed out is a genuine safety concern on airliners, especially what's called clear-air turbulence -- which is unpredictable and has been deadly in the past. Because they are often out of their seats during flight, flight attendants are particularly at risk for injury from unexpected turbulence and quite a few are injured each year. Proposals to install handholds on seats for the use of flight attendants have never advanced very far with the FAA.

With this risk in mind, airlines recommend passengers keep their seatbelts fastened throughout the flight, which cannot be accomplished if passengers are participating in an aerobics class at 38,000 feet. Without throwing too much cold water on the dreamy predictions of the airplane manufacturers, the economics of commercial aviation is such that unused space is wasted space. Boeing and Airbus will probably do on their new designs what they did on previous designs -- fill the space with revenue producing seats and cargo areas.

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