THE SWISSAIR DISASTER

COLUMN ONE
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

Monday, September 7, 1998
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 straight-in approach.

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 its pilots.

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 company.

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 safe flying.

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 signalling.

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" position?

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 answers.

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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