Engine parts pierced protective case in British Airways fire at Las Vegas airport

The British Airways 777 that caught fire Tuesday as it was about to take off in Las Vegas, forcing an emergency evacuation, suffered an uncontained engine failure, an extremely serious rupture of the protective pod around the engine.

A preliminary update issued Thursday by the National Transportation Safety Board cites “multiple breaches of the (left) engine case in the area around the high pressure compressor.”

The cause of the failure is not yet known and the protocol around accident investigations prevents the engine company, GE, and the airplane manufacturer, Boeing, from commenting until a final report is issued.

The high pressure compressor is a system of curved blades rotating around a central spool in the hot engine core. Producing intense pressure and heat, it squeezes (or compresses) the air sucked in by the large fan at the front of the engine.

The NTSB said that investigators found “several pieces of the high pressure compressor spool,” approximately 7 to 8 inches in length, lying on the runway.

This suggests an explosive ejection of the inner parts of the jet engine through the walls of the pod that surrounds the engine.

The purpose of that pod is to contain any parts that fly off in case of a breakup of the engine, so that shards of hot metal don’t pierce either the fuselage or the wing.

Any rupture of that protective case a so-called “uncontained engine failure” is potentially catastrophic, with passengers sitting inside the fuselage and flammable jet fuel inside the wing.

Initial examination of the airplane by NTSB “revealed that the left engine and pylon, left fuselage structure and inboard left wing airplane were substantially damaged by the fire.”

The engine on the British Airways 777-200 was a GE90-85B, an engine so extremely reliable that 777s are allowed to fly more than five hours from the nearest airport.

GE90 engines are the largest and most powerful jet engines in aviation history and exclusively power the 777 which has the best safety record of any of Boeing’s jets.

GE spokesman Rick Kennedy said Thursday that the earlier models of the GE90, including the -85b on the plane in Las Vegas, have an in-flight shutdown rate of only two per million flight-hours.

Fortunately, the failure in Las Vegas happened just short of the plane going airborne.

The engine fire erupted as the jet was accelerating for take off with 157 passengers and 13 crew members on board for a 10-hour flight to London.

In a textbook response, the pilot, Captain Chris Henkey, 63, a 42-year veteran, aborted the takeoff, slammed on the brakes to bring the airplane to a stop, issued a mayday call for firefighting support, and ordered the passengers to evacuate.

All on board were able to exit on emergency escape slides from the right side of the airplane as fire engulfed the left side, badly damaging the aircraft before airport emergency crews extinguished the blaze.

There were a few minor injuries as a result of the evacuation, mostly abrasions, the NTSB said.

Henkey had never previously faced such an emergency. He was only days from retirement, but after the drama in Las Vegas, he’s hanging up his captain’s hat.

“I was supposed to go to Barbados on Saturday and come back next Tuesday and that would be it,” Henkey told England’s Guardian newspaper. “It’s safe to say I’m finished flying.”

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