PARIS, Aug 31 (AFP) - A French judge tasked with finding who was to blame for the 2000 Concorde crash in Paris is to issue an international arrest warrant for a US mechanic employed by Continental Airlines who failed to obey a summons for questioning, law enforcement officials said Wednesday.

The warrant for John Taylor is to be signed by judge Christophe Regnard. Once issued it will automatically designate Taylor as being under criminal investigation for manslaughter, a status that places him one step away from a formal indictment and trial.

Taylor was the mechanic who fitted a non-standard titanium strip to a Continental DC-10 that used the runway at Paris's Charles de Gaulle airport immediately before the ill-fated Concorde.

A French accident inquiry concluded in December that the strip, which fell off the DC-10 and lay on the runway, played a "direct" role in the fiery Concorde crash, which killed all 109 people on the supersonic plane and four people on the ground on July 25, 2000.

The superhard titanium strip shredded one of the Concorde's tyres, sending heavy chunks of rubber through a fuel tank located on one of its delta-shaped wings, causing it to explode and bring the aircraft crashing to earth in a fireball.

Taylor allegedly fixed the titanium alloy part instead of a softer metal strip in Continental's plane maintenance unit in Houston, Texas, even though its use was not sanctioned by US civil aviation authorities, French prosecutors say.

The mechanic, a US citizen, failed to show up in France for questioning on June 17 as required under a summons signed by Regnard.

Taylor's supervisor at Continental, Stanley Ford, was questioned on June 16 in Paris by the French judge but has thus far not been put under criminal investigation.

Continental itself was placed under investigation for manslaughter and injuries in March, but has vowed to fight any charges that may ensue.

A successful prosecution would result in millions of euros in damages against the airline.