PARIS - Investigators probing the crash of an Air France plane off Brazil last year ended their search for its flight recorders with 200 square miles of ocean floor unexplored after misinterpreted data sent them on a six-day detour.

The hunt for the so-called black boxes was called off last night as leases run out on the robot submarines carried by the search vessel Seabed Worker, Alain Guilldou, a spokesman for France’s BEA air-accident investigation bureau, said yesterday.

The ship’s sweep of a zone identified as the likely site of the Airbus SAS A330 wreck was put on hold after analysis of 10 month-old recordings made after the June 1 crash suggested it should switch to a site 40 miles (74 kilometers) away. When later studies showed the sounds probably weren’t from the jet’s “pingers,” almost a week of search time had already been lost.

“As a consequence we won’t be able to cover the last area,” BEA President Jean-Paul Troadec said last week in an interview at the bureau’s headquarters outside Paris. The Seabed Worker will return to port this week so that its two submarines can be returned to their owner in the U.S., he said.

Air France Flight 447 crashed en route from Rio de Janeiro to Paris, killing all 228 people on board. While early findings suggested that the plane’s speed sensors gave false readings when it encountered poor weather, the BEA had said it needed the black boxes in order to establish the crash’s definitive cause.

While Guilldou said a further search hasn’t been ruled out, the probe may now have to rely on other evidence. About 1,000 items of debris and 50 bodies have been recovered.

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