Air Canada Flight 797

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Air Canada Flight 797 was a scheduled trans-border flight that flew on a Dallas/Fort Worth-Toronto-Montreal route. On June 2, 1983(1983-06-02), the aircraft developed an in-flight fire behind the washroom that spread between the outer skin and the inner decor panels, filling the plane with noxious, toxic smoke. The spreading fire also burned through crucial electrical cables that knocked out most of the instrumentation in the cockpit, forcing the plane to divert to an alternate landing field. Ninety seconds after the plane landed and the doors were opened, enough oxygen was available for the fire to flashover, killing the 23 remaining passengers left on board.

Many regulations were implemented around the world to make airplanes safer, including the installation of smoke detectors and emergency lighting leading to exit doors, as well as at least minimal fighting of fires in-flight if necessary.

[edit] Details

At 16:20 CDT (21:20 UTC) on June 2, 1983(1983-06-02),^[1] the Air Canada aircraft registered C-FTLU took off from Dallas/Fort Worth International Airport; it was to make a stop at Toronto International Airport (now Toronto Pearson International Airport) in Mississauga, Ontario, ultimately bound for Dorval Airport (now Montréal-Pierre Elliott Trudeau International Airport) in Dorval, Quebec.

Donald Cameron was the captain and Claude Ouimet served as first officer. While flying over Louisville, Kentucky, an in-flight fire began in or around the rear lavatory of the McDonnell Douglas DC-9-32. The pilots heard a popping sound around 18:51 CDT, during dinner service, and discovered that the lavatory's circuit breakers had tripped. It was not uncommon, however, for an airplane's lavatory circuits to pop occasionally, a problem often preceded by the common aftermath of passengers completing their in-flight meals^[2], so Cameron waited around 8 minutes to give the tripped circuits time to cool down before attempting to reactivate them at 18:59 CDT.^[1]

On the cockpit voice recorder, National Transportation Safety Board (NTSB) investigators heard eight sounds of electrical arcing – likely inaudible to the crew – preceding the initial circuit breaker trips; though a number of wires in the lavatory section were later found with insulation stripped away, investigators were unable to determine whether this insulation damage was the cause of the fire or was caused by the fire. Despite being unable to find the specific shorting wire that caused the arcing sounds and breaker trips nor the exact cause or origin point of the fire, investigators determined that the fire itself was likely an electrical fire that burned behind the wall of the lavatory, with the plane's outer skin serving as a conduit for smoke to seep in through the seams in the interior panels and collect near the apex of the cabin.^[1]

A strong, noxious odor coming from the rear of the plane was first reported to the cabin crew around 19:00 CDT^[1]. Flight Attendant Judy Davidson traced the odor to the lavatory. She attempted to look into the lavatory but was forced back by a thick grey smoke rapidly filling the small room; she then ordered the third ranking crew member to find the chief cabin crew officer to investigate. As Sergio Bernetti sprayed the interior of the affected lavatory with a CO₂ extinguisher, F/A Judy Davidson reported the fire to the captain while F/A Laura Kayarma began urging the passengers on the sparsely-populated flight to come away from the front and rear of the plane and sit closer together in a compact group around the over-wing exits^[1]. At no time did any of the cabin crew mention to either Cameron nor Ouimet that they had yet to see flames, and the one person who had managed to get a good look at the scene – Sergio Bernetti – had not reported seeing anything resembling the traditional causes of airline fires in pre-smoking-ban days: Flames from a trash bin fire or the paper towel dispenser, both of which were commonly set ablaze by passengers who would smoke in the lavatories on long flights.^[1] However, around 19:04 CDT--less than a minute after First Officer Ouimet returned from attempting to investigate the fire, only to find himself being driven back by the thick smoke, which caused him to state strongly that "we better go down", In-Charge flight attendant Sergio Bernetti reported that he thought the fire was probably out because of how much dowsing he gave the lavatory and that "it's gonna be easing up soon".^[1]

Just three minutes later, however, at 19:07 CDT, passengers began smelling smoke in the cabin again, and just two minutes after that – 19:09 CDT – the "Master Breaker" alarm went off in the cockpit, and electrical systems throughout the plane began to fail, including power for the elevator trim system. This made controlling the plane's descent extremely difficult and required a great amount of physical exertion from the pilot and first officer. In addition, the PA system failed, leaving the flight attendants unable to communicate efficiently with the passengers; nevertheless, attendants were able to instruct passengers sitting in the exit rows on how to open the doors, a practice that was not standard on commercial airline flights at the time.^[2]

At 19:20 CDT, Cameron and Ouimet made an extremely difficult emergency landing at the Greater Cincinnati Airport (now Cincinnati/Northern Kentucky International Airport), located in Boone County, Kentucky across the Ohio River from Cincinnati, Ohio. During the evacuation, the overwing aircraft doors were opened, causing an influx of air that fueled the fire. Ouimet escaped through the co-pilot's emergency window shortly after the plane landed, but Cameron, who had exerted so much force to keep the plane under control, was unable to move. Firefighters doused Cameron in firefighting foam through Ouimet's window, shocking him back to consciousness; Cameron was then able to open the pilot's emergency escape window and drop to the ground, where he was dragged to safety by Ouimet.^[2] Less than 90 seconds after touchdown, the interior of the plane ignited, killing 23 of the 41 passengers. The passengers trapped inside the plane died from smoke inhalation and a flash fire. Of the surviving passengers, three received serious injuries, thirteen received minor injuries, and two were uninjured. None of the five crew members sustained any injuries.^[1] The eighteen surviving passengers and five crew members were able to leave the aircraft before the interior burst into flames; Captain Cameron was the last person to leave the plane before the flash fire consumed the plane.^[2] Many of the passengers suffered smoke inhalation and minor injuries. Dianne Fadley, a survivor, stated that "it was almost like" passengers who escaped found "nothing wrong", with a typical injury being a sprained ankle or a broken arm.^[2]

Twenty-one Canadians and two Americans died. Many of the bodies were burned beyond recognition. Almost all of the victims were in the forward half of the aircraft between the wings and the cockpit. Some bodies were in the aisles, and some bodies were still in the seats. Two victims were in the back of the aircraft, even though the passengers were moved forward after the fire had been detected; the disoriented passengers moved beyond the overwing exits and succumbed. The blood samples from bodies revealed high levels of cyanide, fluoride, and carbon monoxide, chemicals produced by the burning plane. ^[2]

Seventy-six maintenance reports had been filed in the plane's logs in the previous year, and four years earlier the plane had suffered an explosive decompression in the rear bulkhead that required rebuilding the tail section and replacing or splicing most of the wiring and hydraulic lines in the back of the plane. Investigators were unable to find signs of arcing in any of the wire splices from the repairs four years earlier, though much of the wiring in the rear of the plane was severely damaged or destroyed by the fire itself.^[2]

[edit] Notable passengers

• Stan Rogers was a Canadian folk singer, known for songs like "Northwest Passage", "The Mary Ellen Carter", "Song of the Candle", and "Barrett's Privateers". He was going home on Flight 797 after attending the Kerrville Folk Festival in Texas. He died in the fire at the age of 33.^[3]
• Also on board was George Curtis Mathes Jr., founder of the electronics company that bears his name. He died in the fire.^[4]

A diagram of Air Canada Flight 797 from the NTSB; the diagram indicates locations of surviving passengers, deceased passengers, and flight attendants

[edit] Aftermath

As a result of this accident and other incidents of in flight fires on passenger aircraft, the NTSB issued several recommendations to the Federal Aviation Administration (FAA), including:

• Safety Recommendation A-83-70 which asked the FAA to expedite actions to require smoke detectors in lavatories^[2];
• Safety Recommendation A-83-71 which asked the FAA to require the installation of automatic fire extinguishers adjacent to and in lavatory waste receptacles^[2];
• Strong recommendation that all U.S.-based air carriers review their fire training and evaluation procedures; procedures were to be shortened and focused on taking "aggressive actions" to determine the source and severity of suspected cabin fires while finding the shortest and safest possible emergency descents, including landing or ditching^[2];
• Installation of track lighting, strong enough to cut through heavy fuel fire smoke, and raised markings on overhead bins to indicate the location of exit rows;
• Strong suggestion that passenger instruction in how to open emergency exits become standard practice within the airline industry^[2]

This 1983 accident is, as of 2009, Air Canada's most recent fatal accident.

Newspapers and other media criticized the actions taken by the crew and said that they took too long to initiate an emergency descent; the initial NTSB report was especially critical of Cameron for not asking about the exact nature of the fire and not immediately initiating emergency descent when the fire was first reported. Cameron admitted in a press conference following the issuance of the NTSB report that he assumed the problem was a bin fire, a common cause of lavatory fires when smoking was still allowed on flights. Pilots and airline personnel throughout the industry petitioned the NTSB to revise its report, and Ouimet wrote a detailed defense of the crew's actions, including the decision to land in Cincinnati instead of Standiford Field Airport in Louisville, Kentucky, the airport closest to where the crew first notified Air Traffic Control in Indianapolis, Indiana that they needed to make an emergency landing. Louisville was too close to be able to descend from cruising altitude to an emergency landing safely, and even landing in Cincinnati was a questionable proposition given Cameron's difficulties in controlling the plane. The NTSB issued a revised version of the report including Ouimet's explanation of the landing decision, though the report was still critical of Cameron's decision not to inquire about the fire itself.^[2] The crew of Flight 797 later received a number of citations from Canadian aviation organizations for their heroic actions in getting the plane down safely.^[2]

All of Air Canada's DC-9s have been retired. As of 2007, it uses the flight number on its Montréal-Los Angeles route.

On 20 December 1983, N994Z, operating as Ozark Air Lines Flight 650, hit a snow plow in Sioux Falls, separating the right wing from the aircraft. The wing from C-FTLU was used to replace the one separated on N994Z after the incident. The aircraft was later sold to Republic Airlines, and acquired by Northwest Airlines after the merger. As of 2006, N994Z has since been retired from the Northwest fleet.

[edit] Dramatization

The episode "Fire Fight" of Mayday (known as "Fiery Landing" of Air Emergency in the USA, "Air Crash Investigation" in Australia) portrays the disaster.

[edit] See also

• China Airlines Flight 120
• Swissair 111

[edit] References

1. ^ ^{a b c d e f g h} NTSB report on Flight 797 crash
2. ^ ^{a b c d e f g h i j k l m} "Fire Fight," Mayday
3. ^ "Artist: Rogers, Stan." Canadian Online Explorer. Retrieved on March 1, 2009.
4. ^ "The Fire Within Flight 797". Time. 13 June 1983. http://www.time.com/time/magazine/article/0,9171,951997,00.html. Retrieved on 2007-07-16. 

• NTSB full accident report
• NTSB brief DCA83AA028

[edit] External links

• A photo of the burning airliner

v • d • e ← 1982 Aviation accidents and incidents in 1983 1984→ Turkish Airlines Flight 158 (January 16) - Air Canada Flight 797 (June 2) - British Airways Sikorsky S-61 crash (July 16) - Air Canada Flight 143 (July 21) - Korean Air Lines Flight 007 (September 1) - Gulf Air Flight 771 (September 23) - Avianca Flight 011 (November 27) - Ozark Air Lines Flight 650 (December 20) Bold indicates accidents resulting at least 50 deaths Orange color indicates the deadliest accident in 1983