You might not be aware of it but there is a serious criminal trial quietly plodding along in France that involves the crash of the Concorde. It has been almost 10 years since the accident after takeoff from Charles de Gaulle airport. The trial started in February and continues as we speak. It is expected to go on until sometime in June or July but it could be over even before you read this.
The trial involves, as defendants, Continental Airlines sued in its corporate capacity, two Continental employees, one a mechanic, and the other the chief of the maintenance team, both American citizens, who were involved with a repair to a DC-10 thrust reverser that was alleged to have lost a wear strip during takeoff.
This strip was fabricated out of titanium by the Continental mechanic to replace the original one made of aluminum. It was approved for installation by the maintenance team chief. The parts catalog lists the original part at under $500. The French court and prosecutors have stated that a new factory part should have been used rather than the locally fabricated part of titanium. They also said that the field repair should have been approved by the FAA and or European Aviation Safety Administration (EASA) personnel. This is of course nonsense because Continental is a 121 carrier and needs no authority from the FAA or EASA to make repairs at home or in the field. However, GE, the maker of the engine, it is reported, seemed to agree with this requirement.
Other defendants include the head of the Concorde Program, accused of failing to strengthen the fuel tanks skins; the chief Concorde engineer for failing to carry out the redesign and strengthening of the lower tank skins; and a senior official of the French aviation authority for failing to understand the importance of and underestimating the seriousness of past incidents involving the puncture of the lower fuel tank skins, which occurred with some regularity on takeoff when the hard rubber of a failed tire impacted the lower skin of the tanks. Concorde stopped using re-molded tires (recapped) after some 65 incidents of burst tires on takeoff. How come the tire manufacturer is not a defendant in this case? I can only wonder how the passengers would have felt about flying Concorde if they knew of the dangerous tire and tank puncture history? I certainly would have declined to fly in it.
The Concorde prosecutor theory alleges that the aircraft hit the short piece of metal with its tires after it fell off the Continental aircraft onto the runway, resulting in it being thrown up against the bottom of the wing or blowing the tire and tire parts impacted and puncturing a fuel tank, starting the fire. The piece is only 17 inches in length overall. The Concorde as we all know did not make it back to the airport and crashed killing all hands.
There are several other theories on the accident, Continental's includes a fire that started before the alleged striking of the metal strip on the runway. Another is simply that a tire failed (which was common on Concorde) and the hard rubber was flung up against the fuel tank surface during takeoff, puncturing it, and that started the fire.
We will probably never know for sure which theory is correct but the French investigators like the metal strip foreign object debris (FOD) theory simply because it throws the blame on somebody else. Interestingly, the government management of the airport was also conveniently left out as defendants. They were supposed to ensure that runways were "swept" before every launch of the Concorde. Anywhere Concorde landed in the world, before every launch, the runway had to be inspected for debris (FOD) before a takeoff could be made.
A key issue that gets little direct attention is the engineering fact that anything thrown up by a tire could puncture the underside of the wing fuel tank, even parts of the rubber tire. The underside of the fuel tank should have been designed for adequate protection to avoid any threat of puncture of the fuel cell on the bottom of the wing. This would seem to be a serious airworthiness item that should have been a concern early in the certification process of Concorde.