Rare engine explosion could have been disaster
Sunday, June 4, 2000
THE RECORD
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By DOUG MOST
Staff Writer
Continental Airlines Flight 60 was barreling smoothly down
the runway at Newark International Airport, a DC-10 carrying 234 passengers
and crew members on a trans-Atlantic flight. At close to 200 mph, with
its wheels just about to lift from the tarmac, there was an explosion under
the left wing.
Passengers on the April 25 flight to Brussels, Belgium, felt the
jolt and were no doubt aware it meant something was wrong. But for veteran
Capt. Doug Schull, his crew, and air-traffic controllers, it marked just
the beginning of 34 nail-biting minutes, as they rushed to dump 90,000
pounds of fuel just 3,000 feet over North Jersey and clear out airspace
to get the plane back on the ground as quickly as possible without a catastrophe.
The troubled aircraft landed safely, and its problems are now
the subject of an investigation by the National Transportation Safety Board.
For reasons that are still unclear, the left-wing engine -- one
of three on the jumbo jet -- had suffered what's known in aviation terms
as an "uncontained engine failure," meaning parts and fragments fly out
of the engine. Such an event is rare -- it has happened only 20 times since
1995 out of some 300 million flights. But in several of those incidents,
pieces such as fan blades penetrated the cabin like bullets. Only luck
prevented that from happening with Flight 60.
"This one didn't sound good right from the start," said Mike Reilly,
the air-traffic controller who handled the plane on takeoff. "You saw smoke,
and you saw he wasn't climbing well. He was really straining to get up
in the air."
Reilly, and others familiar with the incident, praised the flight
crew's handling of a heavy plane that was struggling to fly and difficult
to land. Aviation experts said the troubles that brought the Continental
plane down for an emergency landing at 8:16 p.m. appear frighteningly similar
to those of two other flights that culminated less fortunately after uncontained
engine failures:
United Airlines Flight 232 on July 19, 1989, ended with the DC-10
cartwheeling on the runway during an emergency landing in Sioux City, Iowa,
killing 110 people.
Delta Flight 1288 on July 6, 1996, suffered an engine failure
during takeoff in Pensacola, Fla. Parts were hurled into the left side
of the cabin, killing two passengers.
Continental Flight 60 dropped one piece in flight onto a rooftop
in Moonachie and had a hodgepodge of problems when it came to a stop on
the runway. A hunk of engine casing the size of a desktop dropped off on
the tarmac. All three engines and all of the brakes were damaged and ultimately
had to be replaced. Two tires were blown. A dozen puncture holes, some
the size of pumpkins, were ripped in the cargo hold and the left wing flaps.
The left panel door that protects the landing gear was damaged. Hydraulic
lines to the brakes were severed, and fluid sprayed around the wheel wells.
"This plane was in serious trouble," said J.P. Tristani of Ramsey,
a retired Eastern Airlines pilot and aeronautical engineer who studied
the detailed preliminary report on the incident. "This plane was five minutes
away from being a glider heading into Newark."
Such near disasters in the skies are typically reported in the
media, but Continental Flight 60 received only brief mention, and only
because of the engine part that landed in Moonachie.
At the time, Continental officials played down the incident, saying
only that the plane blew a tire and an indicator light came on, forcing
the pilot to return to Newark.
But a blown tire and indicator light were the least of the DC-10's
problems.
NTSB investigator Paul Cox said he would not comment until he
has all the facts about Flight 60.
But experts said the most likely causes could include anything
from a bird being sucked into an engine, to a mechanical failure inside
the left-wing engine, to a human error related to the maintenance of the
aircraft.
"It just looks like an unusual event," Continental spokeswoman
Catherine Stengel said last week. "We're thankful the training of our crew
allowed them to handle an uncommon situation, and air-traffic control did
a superb job of guiding it back."
She said the plane was repaired and put back into service. "We
took it on a test flight, and it did fine," Stengel said.
Preliminary reports, documents obtained by The Record, and expert
analysis provide a vivid account of just how much Flight 60 struggled from
the moment of its takeoff to its unscheduled landing back at Newark on
April 25.
THE RECORD
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The Flight
Under clear skies at 7:42 p.m., the McDonnell-Douglas DC-10-30,
which made its first flight on Jan. 21, 1973 for Alitalia, pulled onto
Runway 4-L at Newark, which points north, toward Bergen County. The flight
was an hour behind schedule, not uncommon at the airport that leads the
nation in flight delays.
On board for the seven-hour trip were a three-man cockpit crew
-- Schull, First Officer Bill Duus, and Second Officer Bob Mazure -- plus
an 11-member cabin crew and 220 passengers. A typical DC-10-30 has 345
seats.
Since 1995, the jet, which has an average cruising speed of 430
mph, one engine on each wing, and a third on its tail, has had 71 service
reports, with its last major maintenance in 1997, and no accidents, records
show.
"The airplane lined up on the runway, and the captain applied
takeoff power slowly and smoothly," an NTSB report says. "At takeoff decision
speed, there was a loud explosion."
Said Tristani, the retired airline pilot: "That is the most dangerous
time for a pilot to make that decision whether to abort or to go. You have
only a hair of a second. It's the worst time."
The explosion was a catastrophic failure of the left-wing engine.
Immediately, a white "engine fail" light came on and the left-wing engine
decreased its power output by 30 percent. As the plane lifted off, fan
blades from the engine, pieces of engine covering known as cowling, and
chunks of fuselage flew off and punctured two tires as the landing gear
was raised.
Pilots in an Air Portugal plane, along with air traffic controllers,
saw something wrong.
"We had some reports, and it looks like there was some smoke.
You may have blown a couple tires on departure roll," the control tower
told the flight crew. As the DC-10 struggled to climb, the controller ordered
him to "immediately" turn right to avoid an approaching Beechjet corporate
jet.
The DC-10's left engine had become virtually useless and the right-wing
engine suddenly began to vibrate. Investigators say debris from the exploding
left-wing engine shot ahead of the plane on the runway, bounced, and was
sucked into the right-wing engine.
"Pieces were ingested by Engine #3 (right wing) causing extensive
fan blade and nose cowling damage," a Federal Aviation Administration report
says.
The last engine, the one on the jet's tail, sustained minor debris
damage, but its operation was not affected. The plane was now flying with
one engine virtually out, a second at significantly reduced power, and
a third at full power.
"Had one more engine lost a modest 30 percent of its power, that
DC-10 would be coming down, like it or not," said John King, a licensed
airline mechanic who worked for General Electric on the same engines that
the Continental plane was fitted with.
The GE engine that suffered the explosion, known as a CF6, is
one of the more common airline engines. About 5,700 are in service on planes
owned by 162 commercial airlines, according to GE.
The DC-10 could fly on its one good engine, but with it doing
so much of the work, the plane's time was limited to less than an hour,
experts said.
"When you lose two engines on a three-engine plane, you've got
problems," said Reilly, the air-traffic controller.
And there were other problems.
With two tires punctured, and the landing gear not closing completely,
a red light -- the one indicating problems with the left main landing gear
-- was lit on the cockpit panel.
As the jet struggled to climb to 3,000 feet and banked north of
Teterboro over Paterson, the NTSB report says, the crew began to "troubleshoot
the emergency" and found that when power was significantly reduced in the
right-wing engine, the vibration disappeared.
The crew, which could not be reached for comment, probably was
unaware that some of the debris that damaged the right-wing engine also
punctured the body, or fuselage, of the plane. Chunks of metal did not
penetrate the cabin, where the passengers were, but about 10 pieces did
pierce the engine cowling, the cargo hold, and left wing, reports said.
Hydraulic lines that control the brakes were cut, spraying fluid
around the plane's wheel wells.
Realizing he was in trouble, Schull requested a runway to return
quickly for an emergency landing. The crew prepared checklists for what
to do in case they lost the left- and right-wing engines entirely.
"When an emergency like that happens, everybody bends over backward
to clear airspace for them and help them out," said Dan D'Agostino, the
Newark representative to the National Air Traffic Controllers Association.
"They had problems up there. They definitely had their hands full. The
pilots did a good job."
The plane was just six miles from Newark when a piece of an engine
cover -- about 3 feet long, a foot wide, and 15 pounds -- dropped about
1,000 feet onto a Moonachie laboratory roof.
In order to land without having to brake extremely hard, the pilots
had to lighten their plane, which was carrying 120,000 pounds of fuel for
the trans-Atlantic flight. Fuel is usually dumped at 10,000 feet or higher
so it can evaporate in the sky, but Flight 60 was at 3,000 feet, and had
to land quickly, so it is possible some of the 90,000 pounds that were
jettisoned rained down on the ground.
FAA regulations state that a plane may dump fuel no lower than
2,000 feet.
But despite all the problems facing the crew, the landing was
"perfect" Reilly said.
"Everybody was extremely calm and cool," he said. "The pilot did
a real nice job handling the plane. He had some big problems, and he knew
it."
Surrounded by emergency vehicles, the plane came to rest on the
runway parallel to the one from which it had left just half an hour earlier.
Yet its problems were not quite over.
The brakes would not release, forcing the passengers to be taken
off away from a gate. The brake lines were snipped and the plane was towed
to a ramp for inspection. The debris it had left behind on the runway on
departure and on landing was collected for the investigation.
"Bringing an airplane back with two of three engines in trouble,
I don't think I'd like to be on board," C. O. Miller, a former senior investigator
for the NTSB, said after reviewing the board's report. "This was really
close to being a disaster."
The NTSB probe could take as long as six months and will end with
a probable cause based on the facts that were uncovered. The agency then
could make a recommendation on what, if any, follow-up action should be
taken by the FAA.
Staff Writer Doug Most's e-mail address is most@bergen.com
Copyright © 2000
Bergen Record Corp.
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