Evidence Mounts That Jet Engine Failed : More Parts Are Found Near Runway Used by Doomed Airliner

Federal investigators Sunday found mounting evidence that failure of one of its two engines was a major factor in the crash of a jetliner here Friday that killed all 31 aboard.

Officials of the National Transportation Safety Board, which is heading the investigation into the crash of the Midwest Express DC-9, said that more engine fragments were found Sunday beside the main runway at Milwaukee’s Gen. Billy Mitchell Airport.

Jim Burnett, chairman of the safety board, disclosed that a preliminary examination of the plane’s engines--both of which were recovered, largely intact, at the crash site--showed that one had been damaged and was putting out little, if any, power before the jetliner slammed into a wooded grove about half a mile beyond the runway.

Although it was still too early to determine whether the engine fragments found along the runway Saturday and Sunday had definitely fallen from the doomed aircraft, Burnett said, records failed to show that any other plane had had engine problems on the runway in recent months.

“We know one engine was not producing power, and we know that engine was damaged,” he said. “We have found engine parts along the runway. You can draw your own conclusion.”

However, Burnett stressed that “simple failure” of one of the plane’s two Pratt & Whitney JT8D-7 engines probably was not enough to cause the crash all by itself. “You’re supposed to be able to fly even if you’ve lost power,” he said.

Sources close to the investigation said that, under normal circumstances, a DC-9 can lift off the runway on one engine and gain sufficient altitude to remain airborne and make a safe landing at an airport.

Could Hurl Fragments

But safety board sources said that if an engine disintegrates when it fails, it could hurl fragments that might damage control surfaces, rupture hydraulic lines or otherwise cripple a plane and make it veer out of control.

Burnett said the charred remains of the hydraulic lines, cables and other systems connecting the cockpit controls to the DC-9’s flaps, rudder and other control surfaces will be examined today.

Burnett said a preliminary review of the tape from the plane’s cockpit voice recorder yielded the sounds of a stall alarm and a ground-proximity alarm in the final seconds before impact. He said the sounds of these alarms “are not unexpected in a recorder from a plane that has crashed.”

The crash investigation moved forward on several fronts Sunday.

The ground crews sweeping the areas on either side of the runway with metal detectors found fragments from various parts of a jet engine--including compressor blades, shrouds and vanes--all of which apparently could have come from a Pratt & Whitney JT8D, safety board sources said.

Timothy Haeksema, president of Midwest Express, said the line’s flights were resumed as scheduled Sunday, using two DC-9s similar to the plane that crashed.

Safety board officials said they will examine Midwest’s training and maintenance records.

A Federal Aviation Administration report based on an inspection of Midwest completed a day before Friday’s crash, showed no problems with maintenance procedures at the airline, said Rep. Norman Y. Mineta (D-San Jose), chairman of the aviation subcommittee of the House Public Works and Transportation Committee.