A projectile, hurled perhaps by a rear-engine explosion, knocked a hole nearly a foot square all the way through the tail of the United Airlines DC-10 that crashed at Sioux Gateway Airport, killing at least 76 persons, investigators said Thursday.
Hydraulic lines were severed in the tail, and the fluid drained out of all three hydraulic systems on the aircraft, Jim Burnett, a member of the National Transportation Safety Board, told reporters. He said the hydraulic system could not function without the fluid.
The investigators found the rear engine in the wreckage, Burnett said, but its entire fan section and part of its rotor system were missing. He said an explosion that could cause such damage to an engine in flight would be unique.
"This is the first time we've ever seen that," he declared.
In addition to the 76 killed when Flight 232 crashed late Wednesday afternoon en route from Denver to Chicago, rescuers counted 43 persons missing--and 174 survivors.
In Washington, President Bush offered sympathy to victims and their families. He praised the "extraordinary efforts" of those who saved so many lives.
As paramedics searched a cornfield near the airport where much of the wreckage ended up, the living spoke of heroes and miracles. But now the paramedics were hunting for the dead. At nightfall Thursday, they were still removing human remains from the burned-out and mangled tail of the aircraft.
Much of the praise was for Capt. Alfred C. Haynes, a 33-year United veteran, who flew the lumbering jet without full power and without any hydraulics for a desperate 41 minutes while doctors, nurses, policemen and firemen prepared on the ground for a disaster that everyone expected to be far worse.
"Our pilot was a hero," survivor John Transue, 40, told Reuters news service. "He really saved our butts.
"The flames were coming in the airplane while we were skidding," Transue said, clearly in awe. "The whole nose section of the plane just disappeared."
Governor Visits Pilot
Iowa Gov. Terry E. Branstad visited Haynes in the hospital and said the pilot was quite emotional. "Tears came to his eyes when he talked about the number of people who lost their lives," Branstad said. "I told him he did a valiant job."
Other pilots described what Haynes had done.
J. P. Martin, a commercial flier in the Sioux City area who monitored the radio conversation between the cockpit and air traffic controllers, said Haynes or his co-pilot had said: "Nothing really works."
Another commercial pilot, who asked to remain anonymous, said that meant that Haynes could "move the wheel around, but there's nothing there--with no hydraulic power whatsoever, basically all he's got is the engines."
Haynes had "nothing left," a source close to the investigation confirmed. He said the pilot flew the plane by using different power settings on its two remaining engines--one on each wing. By changing and varying engine speeds, this source said, Haynes was able to change the altitude and direction of the aircraft.
Like Rowing a Boat
He "played one of the engines off the other," the source said. He compared it to rowing harder on one oar than on the other to change the direction of a rowboat.
As difficult as that was, Haynes faced even more difficulty when it came time to land the jet, said another DC-10 pilot. Coming in without any hydraulic system whatsoever meant "no slats, no flaps (to slow the plane down)--so he's going like a striped ape. He's got to pull the power off to land, and, the minute he does that, he hasn't got anything to steer the plane with . . . .
"You start losing hydraulic power, you're in a lot of trouble. You haven't got a hell of a lot to fly with."
Other survivors praised the rescuers, who prepared frantically as Haynes kept the stricken jet in the air. The plane carried 11 crew members and 282 passengers, including several infants--but rescuers had no idea at first just how many casualties to expect. They had drilled earlier this year for such a disaster, and the practice paid off.
David J. Greco, the emergency medical director at Marian Health Care Center in Sioux City, activated the disaster plan when the plane was still 32 miles from touchdown.
Hundreds of Rescuers
So swift was the response that hundreds of doctors, nurses, ambulance drivers, policemen, firemen, National Guardsmen and other personnel were at their stations at the Sioux City airport or in local hospitals several minutes before the jet finally crashed.
When the plane hit, it littered the ground with thousands of chunks of debris only inches in size, Greco said. Bodies were strapped three abreast in attached seats that were thrown clear of the fuselage and had rolled down a runway. "They looked like they had been rolling for up to a half mile at high speeds," he said.
Most of the dead appeared to have suffered "terrible injuries to the top of their heads, arms and legs," the areas that had been most exposed during their chaotic tumble, Greco said. Their torsos, cushioned by the seats, were largely intact.
To passenger Kaye Verner of Cincinnati, what happened was a miracle.
"I wasn't aware I was upside down until I saw people in front of me loosen their seat belts and then I saw them drop," Verner said.
"I smelled smoke, and all I could think of was leaving."
Verner fled--to safety.
Several survivors said the miracle was rain. It had soaked the cornfield before the crash.
Kevin Heckman said the wet corn kept fires from spreading.
"It's amazing so many people survived," Gov. Branstad said, noting that it might have been because the rain soaked the soil before impact.
"Maybe the ground was a little softer," he said.
Still others said the miracle was that Flight 232 crashed only seven miles from well-equipped trauma centers that had the time to prepare with blood supplies and other vital necessities.
"If this was outside the area, and we didn't have the resources so close by, if it had been a smaller town an hour away, it would have been tremendous devastation," said Dr. Greco, the Marian Health Center director.
Although the safety agency investigation centered on the rear engine of the plane, a spokesman for General Electric Co., the manufacturer of the engine, said the model used on this DC-10 has an "admirable reliability record."
United spokesmen refused to speculate about the cause of the crash but said the DC-10 had been well maintained.
Burnett, the NTSB member, said investigators would begin reviewing United's maintenance records sometime today. He said a preliminary search showed that the plane's rear engine had been written up on July 18 for a pneumatic system problem.
But Burnett said the problem had nothing to do with hydraulics.
Felt Major Jolt
Flight attendants reported a major jolt about an hour into the flight, Burnett said. He quoted the chief flight attendant, whom he did not name, as describing it as "a severe explosion" that knocked her and other flight attendants to the floor.
The chief flight attendant made her way to the cockpit, where she found the crew "struggling with the controls," Burnett said.
He said a passenger pointed to damage to the right horizontal stabilizer in the tail.
The damage, Burnett reported, amounted to a hole about 10 inches by 12 inches. He said that investigators called it a "projectile penetration."
In addition, he said, there were several smaller holes in the stabilizer.
The investigators found other evidence consistent with an explosion in the rear engine, Burnett said. Cockpit instruments, for instance, showed that crew members had followed severe damage procedures for that engine.
In addition, he said, that engine had used less fuel than the other two--and hence had not run as long.
Moreover, Burnett said, the fuel valve to that engine had been shut, indicating that crew members had turned it off for some reason.
Whatever had knocked the hole in the right horizontal stabilizer had also severed hydraulic lines to its right inboard elevator, Burnett said. He added that the actuator for the elevator was missing altogether.
Fred Farrar, spokesman for the Federal Aviation Administration, earlier had described the plane as suffering a "complete hydraulic failure."
Aviation experts said that debris from an engine explosion might have damaged the body of the plane and the hydraulic system that the pilot uses to steer it.
The plane has three hydraulic systems to provide a margin of safety if one of them is damaged. But Burnett said that, without fluid in all three systems, none of the plane's steering mechanisms would work.
Broke Into Pieces
Crippled by the loss of hydraulic power, the plane pitched violently to the right only a few feet from the ground, scraped its right wing and cartwheeled into a ball of fire. It broke into pieces as it rolled.
Evidence of a mid-air explosion included the fact that one piece of the plane was found 60 miles from the crash site. It was not identified, but it was believed to be part of the tail.
It fell on a farm, Burnett said, and workers moved it into their barn.
Burnett said six witnesses on the ground said the aircraft lost altitude rapidly as it drew near to the airport, approaching steeply and quickly.
He said that Capt. Haynes warned passengers five minutes from the airport, then two minutes and finally in the final seconds to "brace."
It was not possible to tell immediately how high the plane had been flying when it got into trouble, Burnett said, because ground control radar in Omaha, Neb., was out of order when controllers there should have been monitoring the flight.
But Burnett said the altitude of the flight would become available when investigators read data on the plane's flight recorder.
It and the cockpit voice recorder were recovered and taken to Washington for analysis, he said.
Burnett said the tape in the voice recorder was of "fair quality."
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