Vast Search Of Atlantic Ocean For Air France Jet

Other experts doubted a bolt of lightning would be enough to bring the jet down. Some pointed to turbulence as a more dangerous factor.

"Lightning issues have been considered since the beginning of aviation. They were far more prevalent when aircraft operated at low altitudes. They are less common now since it's easier to avoid thunderstorms," said Bill Voss, president and CEO of Flight Safety Foundation, Alexandria, Va.

Voss said planes are built to dissipate electricity along the aircraft's skin, and are tested for resistance to big electromagnetic shocks.

The plane disappeared in an area of the mid-Atlantic ocean not covered by radar. Brazilian, African, Spanish and French air traffic controllers tried in vain to establish contact. The plane was gone.

Within two hours, two Brazilian Air Force planes began a search mission that grew Monday to seven aircraft and three navy ships. But with nothing more to go on than the last point where Flight 447 made contact — about 745 miles (1,200 kilometers) northeast of the coastal city of Natal — they faced an immense area of open ocean, with depths as much as 15,000 feet.