Here's the report that pretty much confirms the lightning strike theory, imo anyways:As several ships trawled the crash site in the Atlantic, Brazil's defense minister said a 20-kilometer (12-mile) oil slick near where the plane, en route from Rio de Janeiro to Paris, went down indicated it probably did not break up until it hit the water.
If true, that would rule out an in-flight explosion as the cause of the crash of Air France Flight 447, Defense Minister Nelson Jobim told reporters.
Also:However, both pilots of an Air Comet flight from Lima to Lisbon sent a written report on the bright flash they said they saw to Air France, Airbus and the Spanish civil aviation authority, the airline told CNN.
"Suddenly, we saw in the distance a strong and intense flash of white light, which followed a descending and vertical trajectory and which broke up in six seconds," the captain wrote.
They couldn't have seen AF447 itself on a stormy night from ,probably, several miles away, but a lightning strike could easily be seen as an intense flash of white light. The fact that a descending trajectory which broke up in six seconds immediately following the intense white flash tells me that an engine was struck, which without the ability to control and compensate due to simultaneous electrical failure, would produce immediate and extreme yaw, roll and wing 'stall'. Those jet engines drive strong electric generators so they are more likely to attract lightning. An explosion (foul play or mechanical failure) would have produced more like an orange fireball or flame I would think. The description of the flash "which broke up in six seconds" could be residual discharge from all the energy absorbed by the plane, or pieces of vaporized/plasmaized engine cowling or internal engine components. That engine may have been ultimately destroyed, but the rest of the plane could easily remain intact.The aircraft's computer system did send about four minutes of automated messages indicating a loss of cabin pressure and an electrical failure, officials have said.
Some investigators have noted that the plane flew through a severe lightning storm. Foul play has not been ruled out.
If it was indeed a lightning strike, maybe the aerospace industry will finally take that possibility more seriously in the future and figure out a way to deal with it/avoid those conditions and provide warnings.