What Caused Swissair Flight 111 to Crash?

What Caused Swissair Flight 111 to Crash?

Auto, Aviation & Transportation

CCGS Hudson searches for Swissair Flight 111 debris on 14 September, with HMCS Anticosti (centre), USS Grapple (right), and a Halifax-class frigate (rear).

On the evening of September 2nd, 1998, Swissair Flight 111 taxis for takeoff from New York’s J.F.K. airport.

Flight 111 was a scheduled international passenger flight from New York City to Geneva, Switzerland.

An MD-11, a jumbo jet, built just seven years earlier by McDonnell Douglas.

McDonnell Douglas’ MD-11 is a wide-body airliner developed in the 1980s.

The MD-11 was designed as a successor to the DC-10, with improved efficiency, range, and passenger comfort.

The development of the MD-11 began in 1983, with McDonnell Douglas proposing a new aircraft to compete with the Boeing 747 and Airbus A300. The MD-11 was designed to be longer and wider than the DC-10, with a new wing and advanced avionics. McDonnell Douglas also incorporated new materials and manufacturing techniques, which allowed for a lighter and more fuel-efficient aircraft.

The MD-11 made its first flight on January 10, 1990, and was certified by the Federal Aviation Administration (FAA) in November of that year. The first MD-11 was delivered to Finnair in December 1990.

McDonnell Douglas MD-11 is taxiing to a position on the flightline at NASA’s Dryden Flight Research Center, Edwards, California, following its completion of the first and second landings ever performed by a transport aircraft under engine power only (on Aug. 29, 1995). The milestone flight, with NASA research pilot and former astronaut Gordon Fullerton at the controls, was part of a NASA project to develop a computer-assisted engine control system that enables a pilot to land a plane safely when its normal control surfaces are disabled. The Propulsion-Controlled Aircraft (PCA) system uses standard autopilot controls already present in the cockpit, together with the new programming in the aircraft’s flight control computers. The PCA concept is simple. For pitch control, the program increases thrust to climb and reduces thrust to descend. To turn right, the autopilot increases the left engine thrust while decreasing the right engine thrust. The initial Propulsion-Controlled Aircraft studies by NASA were carried out at Dryden with a modified twin-engine F-15 research aircraft.

The MD-11 had a difficult start. With a series of crashes and incidents that damaged its reputation including the Swissair event.

In 1994, an MD-11 operated by FedEx crashed during landing at Newark Liberty International Airport, killing the crew. In 1996, an MD-11 operated by China Airlines crashed during landing in Hong Kong, killing 223 people. Both accidents became attributed to pilot error.

Despite these setbacks, the MD-11 proved to be a capable and popular aircraft. Furthermore used by a number of major airlines such as Delta Air Lines, KLM, United Airlines and of course Swissair. The MD-11 also found success as a cargo aircraft, with FedEx, UPS, and other companies using it for freight operations.

Production of the MD-11 ended in 2000, with a total of 200 aircraft built. McDonnell Douglas was acquired by Boeing in 1997, and the MD-11 was eventually replaced by the Boeing 777 and 787. However, the MD-11 continues to operate in some parts of the world, and is regarded by many as a classic aircraft.

At 8:18 p.m., Eastern Time, Flight 111 takes off, then, about an hour after takeoff, some smoke enters the cockpit.

And then, according to Operations Group Chair, Transportation Safety Board of Canada Mark Clitsome: “The first officer noticed an odor, mentioned it to the captain and, uh, the captain said look. The first officer said that he’d get up and take a look at it. And he looked around, and he couldn’t see anything. There was nothing more out there. And the captain then called the flight attendant from the first class section to come forward and asked her if she had seen any smoke or smelled anything, and she said there was nothing in the first class section where she was working.”

Profile photo of Mark Clitsome FRAeS
Mark Clitsome | LinkedIn

However, the pilots sadly decide to dismiss it as a common air conditioning problem. But, then again, two minutes later, at 9:14, air traffic control receives a transmission from Swissair 111 declaring “Pan, Pan, Pan”—the international urgency call, indicating trouble but not a threat to life.

The pilot requests a place to land. The transmission becomes obscured by his oxygen mask. As a result of being 300 miles past Boston’s Logan Airport. The ATC radios to suggest Halifax Airport. Which lies some 60 miles away. And the pilot accepts. As a result, Swissair 111 becomes passed over to the Halifax air traffic controller.

Halifax’s runway 06 becomes readied for an emergency landing by the Swiss carrier.

Clitsome goes on to report that:

“The air traffic controller notified them that they were 30 nautical miles to the runway. However, they were still not ready, at that altitude, to land, so they had to lose some more altitude. Then the pilots also mentioned to the air traffic controller that they needed to dump some fuel, and so the controller turned them back towards the ocean to do that.”

Swissair 111 flies towards the Atlantic Ocean and radios again to Halifax. A warbling sound in the background indicates that the autopilot became disconnected. Both pilots declare emergency. It’s 9:25.

Then for the next six minutes there is no further communication.

At 9:31, Eastern Time, Swissair Flight 111, with 229 people aboard, crashed into the freezing dark waters off Nova Scotia at 560 kilometres an hour into St. Margaret’s Bay.

Fisherman Scott Hubley raced to the scene and told CBC; “It was a black old night,” he said. “We started picking up luggage, clothes, food trays — whatever’s on a plane — and then it got more graphic. Stuff you’ve never seen before, but you knew what it was.”

The cause of the crash was determined to be a combination of factors, including equipment failure and human error.

The investigation into the crash found that a fire had started in the aircraft’s cockpit and had spread rapidly, causing critical systems to fail and leading to the loss of control of the aircraft. The fire was traced back to faulty wiring in the in-flight entertainment system, which had overheated and ignited flammable insulation material.

However, the investigation also found that the crew had not recognized the severity of the situation.

And had not taken appropriate actions to contain the fire and land the aircraft safely. The cockpit voice recorder revealed that the crew had spent several minutes discussing the source of the smoke and had not declared an emergency or requested priority landing until it was too late.

Other contributing factors to the crash included the complexity of the aircraft’s systems and the lack of clear emergency procedures for dealing with such a situation.

The investigation led to significant changes in aircraft safety regulations, including improvements in the design and maintenance of electrical systems, as well as improvements in crew training and emergency procedures.

The Swissair Flight 111 crash remains one of the deadliest aviation disasters in Canadian history in addition a tragic reminder of the importance of aircraft safety and the need for continuous improvement in aviation technology and procedures.

Clitsome believes the final crash was due to a complete disorientation on the part of the remaining first officer who was flying the plane. We know from the pilot’s seat being retracted that he likely attempted to fight the fire. And might have become disabled.

“Swiss Air 111 entered into “a ‘black hole’ effect.”

“If you’re not flying by instruments, and you’re flying by using outside visual references, it’s very difficult to discern up from down and left from right.”

Desperately searching for Halifax airport, fire raging in a smoke- and fume-filled cockpit, black sky above and black sea below. Sadly, the first officer likely unknowingly rolled the plane over onto its side. And as a result entered a dive where recovery became impossible.

Lastly, one of the lost passengers include real estate mogul Nikos Kefalidis. A developer and founder of KLM Construction Inc. The New York Times reported that, “President Clinton sent a message of condolence to a memorial service for Mr. Kefalidis.”



Many pictures & captions from: Fishermen who raced to Swissair crash can’t forget ‘a black old night,’ 20 years on | CBC News

Avionics Times

Canadian Transportation Agency – Canada.ca

What Caused Swissair Flight 111 to Crash?