The first bodies of those killed in the Air France crash in the Atlantic have been flown back to Brazil. The remains of 24 passengers have been recovered from the sea; they have been brought back to Fernando de Noronha for forensic examination along with debris from the downed jet as investigators try to discover why the plane came down.Rescue crews have pinpointed the crash site, and more wreckage. It includes Flight 447’s tail, the largest piece of the plane so far found. Everything will be taken back to Brazil for examination as aviation experts piece together the last minutes of the Airbus’s flight. It’s still not known why the plane crashed. Theories abound: one says the air speed sensors may have iced-up and failed, causing the plane to fly faster or slower than needed. Either case could have provoked the crash. Air France announced that speed sensors on all its long-haul Airbus fleet would be replaced today, after pilots said they would refuse to fly planes with suspect equipment.