Flying The Flame-Filled Skies

American Airlines flight 574 was just five minutes out of San Juan, bound for Miami, when the pilots reported a fire in the left engine, reports CBS News Correspondent Bob Orr.

With flames clearly visible, the Airbus A-300 with 251 people aboard turned back for an emergency landing.

Moments later the jet touched down with the engine still blazing. As fire crews rushed to snuff out the flames, passengers hurtled down emergency chutes to safety. Only a few were even slightly injured.

Engine fires are rare, but federal investigators are particularly concerned about this one -- because of what did not happen when the jet was still in the air.

American Airlines says the pilots -- following emergency procedures -- immediately shut off the fuel to the burning engine and triggered the engine's fire extinguishers.

However, while the extinguishers appeared at first to do their job, the fire quickly re-ignited and continued to burn just beneath the wing, which was filled with thousands of gallons of fuel.

Veteran investigators say that if the engine fire had erupted just a few minutes later -- with the jet farther from the airport -- it could have been catastrophic.

The engine involved in the incident is made by General Electric and is used on 750 planes around the world.

While the engine has a reputation as a reliable workhorse, NTSB investigators want to know why, in this case, the critical fire suppression system apparently failed.

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