THE SWISSAIR DISASTER
Monday, September 7, 1998
Could the pilot have landed the plane?
That's going to be a question that aviation experts -- and
lawyers -- will put high on their lists
By Paul Koring
Peggys Cove, N.S. -- Moncton air-traffic control to Swissair 111: "You've
got 30 miles to fly" to the Halifax runway threshold.
Swissair 111: "We need more than 30 miles."
At about 10:20 p.m., Captain Urs Zimmerman was six minutes into an emergency
descent, just crossing the Nova Scotia coast about 5,000 metres above
the tiny fishing village of Prospect. The big MD-11, only eight years
old and impeccably maintained by one of the world's premier airlines,
was lined up almost perfectly for a straight-in approach to Runway 06,
the longest at Halifax International Airport.
But Capt. Zimmerman was too high and too heavy for a normal approach.
What he didn't know or didn't foresee was that there wasn't time for
a normal approach. He had only about five minutes -- perhaps a little
longer -- of flyable aircraft left.
In the coming weeks and months, pilots all over the world will strap
themselves into sophisticated MD-11 simulators and try it. In ungainly
white boxes, mounted on hydraulic stilts, sitting before exact replicas
of MD-11 instrument panels and looking out through windows at uncannily
accurate representations of what Capt. Zimmerman would have seen if he
had crossed Halifax toward the safety of a long, wide runway flanked by
bright lights, they will try to bring Swissair Flight 111 to a safe landing.
The outcomes will be endlessly debated where pilots meet, among accident
investigators, and most certainly in the courts.
The stakes are huge, and they go far beyond the machismo of pilots who
claim that it could have been done, or that at least Capt. Zimmerman should
have tried -- that a bent aircraft, or even a wrecked one strewn across
Halifax airport, would have at least offered a chance of survival to some
of the 229 people on board.
As the huge lawsuits that inevitably follow all major aircraft disasters
wend their way through the courts, the apportioning of blame and the size
of the payouts will, in part, depend on whether the pilots erred in going
by the book and whether they should have attempted a risky and difficult
What is certain is that crippled aircraft, some dangerously overweight,
others without power or electrics, others with their flight-control systems
grievously impaired, have been landed safely. Pilots who throw away the
flight manuals and get themselves and their passengers down safely against
the odds are justly lionized as heroes.
There was the United Airlines crew who in July of 1989 brought a DC-10
to a flaming, controlled crash at Sioux City airport in Iowa, steering
only by varying engine thrust.
More than 180 of the 293 on board survived. And the Aloha pilots who landed
their crippled Boeing 737 after one-third of the fuselage roof tore away
in April, 1988. Everyone on board walked away except a flight attendant
who was sucked out of the gaping hole.
Or the Air Canada crew who successfully landed their burning DC-9 at
Cincinnati in June of 1983. Twenty-three of the 46 people on board survived,
and the pilots were given medals despite being faulted by the U.S. National
Transport Safety Board for wasting between "three and five" minutes
before declaring a full emergency and heading for the nearest runway.
Aviation's annals are filled with tales of dead pilots who failed to
react fast enough to what seemed, at first, to be a minor problem.
In many major airline disasters, nothing the pilots could have done would
have made any difference. When a terrorist bomb shatters an airliner,
like the Air-India flight that went down off Ireland in June of 1985,
killing 329 on board including 280 Canadians, or a fuel-tank explosion
destroys an aircraft in mid-flight, as happened to TWA's Flight 800 off
Long Island, N.Y, two years ago, there is no question of pilot "what-ifs."
But in accidents like last week's Swissair crash off Peggys Cove, N.S.,
both the sequence of systems failure and the pilot's decisions will come
under intense scrutiny.
Not surprisingly, Swissair already asserts that Capt. Zimmerman could
not have managed a steep, fast, overweight, straight-in approach. Even
before anyone knows what troubles he was facing other than that there
was smoke in the cockpit, the airline has flatly stated that it was impossible
to land the MD-11 safely. That may have more to do with positioning for
the eventual legal wrangle over whether a flawed aircraft -- and therefore
the manufacturer, McDonnell Douglas, now owned by Boeing -- is at fault,
rather than the airline that maintained the plane and set the rules for
Swissair's chief pilot designate, Rainer Hiltebrand, said company pilots
have already tried and failed to successfully land an MD-11 on a straight-in
approach using the company's simulator. "The aircraft would have been
too high and too heavy to perform a direct approach," confirmed Philippe
Bruggisser, chief executive officer of SAirGroup, the airline's holding
In any event, Capt. Zimmerman didn't try.
The first indication that anything was amiss aboard Swissair 111, en
route from New York to Geneva, came at 10:14 p.m. "Pan, Pan, Pan,"
the crew radioed to air-traffic controllers. "Swissair 111 heavy (heavy
means a large jet in air-traffic-control jargon, the MD-11 being the second-largest
intercontinental jetliner after Boeing's mammoth 747) is declaring Pan,
Pan, Pan. We have smoke in the cockpit and request deviate immediate right
turn to a convenient place, I guess Boston."
Two things in that first message suggest that Capt. Zimmerman, a senior
instructor with long experience on the MD-11, and his co-pilot, Stephan
Leow, didn't regard the situation as dire. "Pan, Pan, Pan" is
a step below the full-blown emergency signal of "Mayday," and
they asked to go to an airport more than 500 kilometres away and requiring
a complete U-turn.
Student pilots are taught that a sense of current location, including
an awareness of the closest alternative landing sites, is essential for
Although it is not included in the partial transcripts of radio conversations
between Swissair 111 and Moncton's flight-control centre, the air-traffic
controller immediately gave permission to divert to Boston. The big jet
began a slow turn to the right. At the same time, the controller pointed
out that Halifax airport, a major international facility with emergency
equipment, an 8,100-foot runway and a fully staffed tower with controllers
handling landings and takeoffs, was much closer.
In fact, it was about 110 kilometres directly in front of the Swissair's
original course, and as it happened, the active runway was ready to receive
flights from the southwest.
"Would you prefer to go to Halifax?" the controller asked, which
is about as far as a ground controller can go in suggesting that a pilot
might be ignoring the obvious. Air-traffic controllers provide clearance
and guidance, but the flight crew holds absolute responsibility.
"Affirmative, for Swissair one eleven . . . Prefer Halifax,"
replied the Swissair crew. The MD-11 pulled out of its right-hand turn
into a shallow left, headed directly toward the airport.
The time was about 10:15, although the Transport Safety Board of Canada
leading the investigation has yet to release full records of the radar
tracking which will show times, altitudes, speeds and directions until
the plane's transponder ceased some time after 10:24.
Capt. Zimmerman had also put the MD-11, flying at 33,000 feet, into a
steep descent, shedding height at the rate of more than 3,000 feet a minute,
according to Vic Gerden, the lead investigator for the Transportation
Safety Board. He was also likely beginning to slow the big jet from a
cruising speed of nearly 800 kilometres an hour.
Minutes later, Capt. Zimmerman crossed the coast. The controller told
him he was 50 kilometres from the runway threshold, but the Swissair crew
said it was not enough, believing the plane was too high and too heavy
to attempt a landing.
The controller vectored the aircraft left, veering north. A little later
the jetliner reported that it "must dump some fuel" to bring the
MD-11 down to the maximum allowable landing weight and asked for a "left
or right turn."
The response: "Turn left heading of 200 degrees and advise me when
you are ready to dump."
Still apparently in control of a flyable aircraft, Capt. Zimmerman executed
a precise 180-degree turn. He was now headed out to sea, away from the
airport and at right angles to its active runway, hardly the course a
pilot would take if he knew the end was near.
Then, at 10:24 p.m. (although it remains unclear whether the cockpit
clock was precisely the same as the air-traffic control timings), Swissair's
crew gave the first indication that their situation had become dire.
"We are declaring an emergency at time zero one two four. . . . We
are starting vent now. We have to land immediately."
The term vent has investigators puzzled. Did the pilot mean he was dumping
fuel through the vents in the wings designed for that purpose? Or that
the smoke had got so bad the crew had actually opened the side windows
in the cockpit?
Nothing further was ever heard from the stricken aircraft. What is known
is that it continued on course out to sea, level at about 9,700 feet,
and for another minute or so the transponder kept responding to the radar
interrogation with altitude, speed and heading information. Then it ceased
For about another six minutes the aircraft flew, a tight counter-clockwise,
irregular spiral. Now it was showing only on primary radar, which simply
sends a signal out and records the reflection of moving metal objects
aloft. Despite the dire "We have to land now" there was no turn
toward the airport, nor any altitude loss indicating the pilots were preparing
for an emergency ditching.
There was no evidence as to whether Flight 111 flew the last steeply
banked circle under control and then suddenly dived into the sea or whether
the big MD-11 was completely beyond control.
Perhaps the pilots had been overcome by smoke or toxic fumes. Perhaps
they had been forced to flee raging flames in the cockpit, and the last,
short, straight and level leg to the south-southeast was flown on autopilot
until it too failed as a result of the craft's dying electrics.
All indications, provided by the fragmentation of bodies and wreckage
recovered, are of an enormous final impact.
Anecdotal evidence from witnesses on the ground who heard the big jet
roar overhead suggests that the engines were still running (although the
noise sounded laboured) but that the electrical system had failed. Witnesses
say they saw no lights, either navigational or from the cabin, as the
MD-11 thundered through the night sky on its last circuit.
Many of the answers lie in the state-of-the-art flight recorders. Those
two "black boxes" -- actually bright orange and designed to survive
horrendous impact, searing post-crash fires and deep-ocean pressure --
contain the cockpit conversations between the pilots and data records
of more than 100 parameters. With the data recorder recovered from the
ocean floor yesterday, it may now be possible to program MD-11 simulators
to determine whether Capt. Zimmerman could have brought his aircraft down
safety at Halifax in the time available.
The condition of the box is not yet known. But with electrical failure,
it is possible that both recorders' crucial data may end not when Swissair
111 hit the sea, at about 10:30 p.m. or perhaps a minute later, but six
minutes earlier, when the transponder signals faded from radar scopes
in Moncton. If that is the case, then the details of the last minutes
aboard the stricken jetliner may be even more difficult to piece together.
Some of those questions will be crucial, not just to investigators seeking
to prevent similar accidents but to the legions of lawyers and litigants
who always gather like vultures after an aviation disaster.
For instance, did the passengers face their deaths in darkness, as the
cabin filled with choking smoke or toxic fumes? Did the end come suddenly
in a quick final plunge, or in an agonized, staggering circuit as terrified
passengers donned life jackets and clasped their knees in the "brace"
Especially in U.S. courts, where many of the inevitable cases will be
heard given that so many passengers were American and that both the aircraft
and the engine were made by U.S. companies, such issues are crucial in
determining the amount of awards for pain and suffering.
Accident investigators refuse to indulge in speculation. "I don't
deal in maybes," Mr. Gerden of the Transportation Safety Board has
said several times at news conferences where the what-ifs fly thick and
fast from the media.
But the questions won't go away. The relatives of those killed and their
lawyers, as well as pilots everywhere and the flying public, will want
Especially in an accident like this one. Everyone in air transport likes
to boast that being aboard a modern jetliner is the safest place in the
world. Safer than in the home, far safer than driving a car. And passengers
aboard premier airlines such as Swissair, flying fleets of modern jetliners
on routes like the busy but well-controlled North Atlantic run, are supposed
to be the safest of all.
Aside from the Air-India crash, caused by terrorists, there wasn't a
transtlantic crash for decades. Now, in barely two years, two huge jets,
both flown by major Western carriers, first TWA 800 and now Swissair 111,
have plunged into the sea, killing everyone on board.
The TWA jet was old, a first-generation Boeing 747, and the precise cause
of the crash remains undetermined; but it is known the centre fuel tank
exploded, possibly ignited by a spark from worn wiring.
The Swissair MD-11 had made only 6,400 flights for a total of 35,000
hours, relatively young for a jetliner. It was being flown by an experienced
crew for a major airline with a reputation for high standards and maintenance
expertise on the MD-11. In fact, Swissair, one of the few carriers that
use MD-11s as their major long-haul flagship, performs maintenance on
MD-11s for other carriers.
Crashes like this one just aren't supposed to happen.
THE LAST 16 MINUTES
The following is a partial transcript of the final conversations between
the crew of Swissair Flight 111 and the air-traffic-control centre at
Moncton, N.B. as released Saturday by the Transportation Safety Board.
1. 10:14 p.m., 33,000 ft, 570 m.p.h. Swissair Flight 111: Swissair 111
heavy, is declaring Pan Pan Pan (a code for a less than serious emergency).
We have smoke in the cockpit, request deviate immediate right turn to
a convenient place. I guess Boston.
2. Controller: Would you prefer to go into Halifax? Flight 111: Affirmative
for Swissair 111...prefer Halifax from our position. (Note: Halifax is
70 nautical miles, Boston 300 nautical miles. Aircraft starts descent
from 33,0000 feet.)
3. Controller: OK, active runway at Halifax is zero six, should I start
you a vector for six? Flight 111: Yes, vector for six will be fine, Swissair
111 heavy. Controller: Turn left heading zero three zero.
4. Controller: You've got 30 miles to fly to the (runway) threshold.
Flight 111: We need more than 30 miles...Controller: Turn left...lose
some altitude...Flight 111: Roger we are turning left...
Flight 111: We must dump some fuel. We may do that in this area during
descent. Controller: Ok. Flight 111: OK, we are able for a left or right
turn toward the south to dump. Controller: Roger, turn left heading of
200 degrees and advise me when you are ready to dump...
6. Flight 111: We are declaring an emergency at time zero one two four
(9:24 p.m. EDT)...we are starting vent now. We have to land immediately.
Controller: Swissair 111, you are cleared to commence your fuel dump on
that track and advise me when the dump is completed...
7. Controller: Swissair 111 you are cleared to start fuel dump. (Note:
There were no further communications from Swissair Flight 111. Approximately
six minutes later, the aircraft contacted the water.)
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