The importance of Flight 447's missing black boxes

Black box data can provide key clues to how the crash happened, information that's vital for future airline safety and design.

If the flight data recorders from Air France Flight 447 are never recovered – as seems increasingly possible – their absence will make it difficult to figure out what caused the accident and to apply any lessons for improving future air safety, say some aviation analysts.

The so-called black boxes, which are actually bright orange, contain recording equipment that hold keys to understanding what happened in the last minutes aboard the Airbus 330-200 aircraft before it apparently broke up over the Atlantic Ocean June 1.

The Airbus was on a routine flight from Rio de Janeiro to Paris with 228 people aboard. There were no survivors. The flight captain and the steward were among the 50 bodies recovered so far, according to Air France.

Black box data include recordings of the pilots' last words in the cockpit, as well as a computerized record of how key parts of the plane were functioning. Combined with physical information gleaned from the wreckage, the data help investigators piece together what happened – and, from that, to recommend changes either to aircraft design or pilot training to improve future aviation safety.

Without that data or more recovered wreckage, aviation analysts say, there's little to go on other than speculation.

"That would probably cast a cloud over a number of things that conceivably could be cleared up with greater information and physical evidence – which may be unfair," says Robert Mann, president of R.W. Mann & Co., an aviation consulting firm in Port Washington, N.Y.

"It may also be insufficient to really force more fundamental changes" to improve safety, he says. "In the absence of either more physical evidence or the data recorders, we're going to miss the opportunity to do both of those things."

The Airbus 330-200 has design and material features that are increasingly used in other new aircraft, making it especially important to find out what happened.

Some analysts have looked at the possibility that on-board computer problems contributed to the accident. The Airbus is a fly-by-wire aircraft, which means the flight controls are electronically controlled. The system's computer is designed in such a way that, if a pilot makes an error or an unusually strong wind gust throws the plane off course, the computer will automatically right it, overriding the manual controls. Several Airbus planes have had problems with what are called "uncommanded movements," initiated by the computer.

Another concern has to do with the parts of the Airbus 330-200 made of composite materials, including the rudders and the tail fins known as the vertical stabilizers. These materials, engineered from spun fabric and resins, are believed to be as strong if not stronger than some metals. But they are also more difficult to test for potential problems and can delaminate internally, weakening the materials.

New generations of planes are being made with more sophisticated computers and more composite materials than in the past. So understanding what happened to Air France Flight 447 could be vital to future aviation safety, analysts say.

"Given the quantum leaps we're making in becoming more reliant on [computer-controlled] aircraft that cannot revert to manual control, and a predominance of composite structures [in aircraft construction,] the [Air France Flight 447] data would be an important one to have to tell us it's OK to continue to move in those directions," says Mr. Mann, "or that maybe we've already moved too far and the certification standards haven't kept up."