No Conclusions Yet in Air France Flight 447 Crash Probe

French investigators said Wednesday more than 400 pieces of Flight 447 have been recovered in a painstaking search in the Atlantic but no conclusions have yet been reached in the probe.

“If we had concluded or excluded something, we would have told you,” said Paul-Louis Arslanian, head of the French air accident investigation agency BEA.

Still, he expressed “a little more optimism” in finding clues to what caused the crash as discovery of more debris narrowed the vast search zone off the northeast coast of Brazil.

The Air France Airbus A330 crashed into the ocean May 31 with 228 people aboard after running into thunderstorms en route from Rio de Janeiro to Paris.

Speaking at BEA headquarters in the Le Bourget air field outside Paris, Arslanian said more than 400 pieces of wreckage have been recovered and are being gathered in a hangar in Recife, Brazil.

He said the debris came from “all zones” of the plane, but did not describe them in detail or say what proportion of the entire Airbus A330 has been retrieved.

Still missing are the plane’s two black boxes, its flight data and voice recorders, thought to be deep under water. The black boxes provide information about what happened to the plane before and during the crash. They will emit signals for at least another two weeks, after which the pings will fade.

Arslanian said Brazilian authorities have not released to the French the autopsy results from the bodies recovered so far, although he expects they will be. With another body found Tuesday, 50 have been recovered so far.

The chief French medical investigator also worked on autopsies of victims of the TWA Flight 800 crash in July 1996.

The French are leading the crash investigation, while the Brazilians are leading the rescue operation.