Warning Signs Ignored From Smoke to Inferno — Air Canada 797’s Fight for Survival

On June 2, 1983, Air Canada Flight 797, a McDonnell Douglas DC-9-32 registered C-FTLU, was cruising from Dallas/Fort Worth toward Montréal with a planned stop at Toronto when a fire developed in the aft lavatory. What began with tripped circuit breakers and a faint odor progressed into heavy smoke, an emergency descent and a catastrophic cabin fire. The aircraft landed at Greater Cincinnati Airport, but the fire intensified during the evacuation and 23 people died.

The first warning

At 18:51 EDT, the flight crew heard a popping sound from the rear of the aircraft and found the aft-lavatory circuit breakers tripped. Captain Donald Cameron attempted to reset them, but the breakers would not remain engaged. About nine minutes later, a passenger reported an unusual odor to a flight attendant.

The aft lavatory was opened partially and light gray smoke was seen. Chief flight attendant Sergio Benetti entered with a carbon-dioxide extinguisher and discharged it into the lavatory. The cockpit was then informed that there was a fire.

The fire spreads

First Officer Claude Ouimet went aft to investigate but found smoke filling several rows. The crew initially had incomplete information about the fire's location and severity. The NTSB later identified this conflicting information and the crew's underestimation of the fire as important parts of the accident sequence.

At 19:08 EDT the crew declared a Mayday and began an emergency descent from about 33,000 feet. The descent rate exceeded 6,000 feet per minute. As the aircraft descended, electrical systems progressively failed, including the transponder and important flight instruments, leaving ATC to assist with a no-gyro radar approach.

Landing and evacuation

The DC-9 landed at Greater Cincinnati Airport with the fire still active. The aircraft stopped and evacuation began, but the fire spread rapidly through the cabin. The smoke and heat became severe enough that many passengers could not reach exits. The accident ultimately killed 23 people, while 23 passengers and crew survived.

What the NTSB concluded

The NTSB first issued its report in 1984 and later revised it after reconsideration. The superseding report, NTSB/AAR-86/02, identified a fire of undetermined origin, the flight crew's underestimation of its severity and conflicting information about its progress as the probable-cause elements. It also identified the time taken to evaluate the fire and decide to begin the emergency descent as a contributing factor.

The ignition source was never conclusively established. The accident nevertheless drove major changes in cabin-fire detection, lavatory fire protection and evacuation-related requirements.

The final approach and evacuation

The investigation found that three flush-motor circuit breakers had tripped about 11 minutes before smoke was detected. The captain initially received conflicting reports about whether the fire was improving, and the aircraft landed at Cincinnati rather than Louisville, where the FAA summary says the landing could have occurred three to five minutes sooner. These details became central to the investigation's assessment of the delay and the information available to the flight crew.

The FAA's historical accident summary records the sequence in detail: the fire was reported at about 19:03 EDT, the emergency was declared at approximately 19:08, and the DC-9 landed at 19:20. After the aircraft stopped, occupants began evacuating while firefighters moved into position. About 60 to 90 seconds after the exits were opened, a flash fire swept through the interior.

“a fire of undetermined origin”

Accident Facts

The NTSB report uses Eastern Daylight Time for the event chronology.

Sources

• NTSB: Air Canada Flight 797 investigation DCA83AA028
• FAA: Lessons Learned: Air Canada Flight 797