A French appeals court overturned manslaughter convictions against Continental Airlines and a mechanic for the July 2000 crash of an Air France Concorde that killed 113 people, ruling Thursday that their mistakes did not make them legally responsible for the deaths.

The crash hastened the end for the already-faltering supersonic Concorde, synonymous with high-tech luxury but a commercial failure. The program, jointly operated by Air France and British Airways, was taken out of service in 2003.

In the accident, which occurred on July 25, 2000, the jet crashed into a hotel near Paris' Charles de Gaulle airport soon after taking off, killing all 109 people aboard and four on the ground. Most of the victims were Germans heading to a cruise in the Caribbean.

A mistake made weeks earlier and thousands of miles away by a Continental mechanic in Houston played a crucial role in the crash, the court found.

Concorde's design vulnerable to shock

According to the original ruling, the mechanic fitted the wrong metal strip on a Continental DC-10. The piece ultimately fell off on the runway in Paris, puncturing the Concorde's tire. The burst tire sent bits of rubber into the fuel tanks, which started the fire that brought down the plane.

'The court says the plane shouldn't have flown. It did fly, but no conclusion is drawn.'—Stephan Gicquel, head of a group of victims' families

But the Concorde's design left it vulnerable to shock, according to judicial investigators who said officials had known about the problem for more than 20 years. The lower court ruled that though French officials had missed opportunities to improve the Concorde over the years, they could "be accused of no serious misconduct."

Stephane Gicquel, head of a group of victims' families, said Thursday's ruling left them with "a sense of powerlessness."

"The court says the plane shouldn't have flown. It did fly, but no conclusion is drawn," he said.

Continental's initial conviction included €2M in fines

A French court initially convicted Continental Airlines Inc. and the mechanic in 2010 for the crash, and imposed about €2 million ($2.7 million) in damages and fines on the carrier.

Parties including Air France and Continental compensated the families of most victims years ago, so financial claims were not the trial's focus — the main goal was to assign responsibility. In France, unlike in many other countries, plane crashes routinely lead to trials to assign criminal responsibility — cases that often drag on for years.

"This was a tragic accident and we support the court's decision that Continental did not bear fault," Megan McCarthy, a spokeswoman for Chicago-based United Continental Holdings Inc., said in a written statement. Continental merged with United in 2010.

At the time it was launched, the Concorde supersonic jet was the height of luxury, flying between New York and the European capitals of London and Paris in less than four hours, instead of a standard flight of over seven hours. Flying west, British Airways boasted, the flight's well-heeled travelers could effectively arrive at their destinations before they left.

In the years it took French judicial investigators to work their way to trial, amassing 80,000 pages of court documents, the Concordes were revamped, retired and finally sent to museums.