AOPA News: Air Safety Foundation Says Carbon Monoxide Accidents Rare But Deadly


Aircraft Owners and Pilots Association
421 Aviation Way
Frederick, MD 21701

January 23, 1997

Warren Morningstar

Air Safety Foundation Says Carbon Monoxide Accidents Rare But Deadly

Offers Safety Advice

FREDERICK, MD – The AOPA Air Safety Foundation says accidents caused by carbon monoxidepoisoning are extremely rare, but recommends pilots install inexpensive CO detectors intheir aircraft. ASF also suggests pilots and mechanics redouble efforts to recognize andprevent aircraft exhaust system leaks.

"A search of the Air Safety Foundation accident database revealed only twoaccidents caused by carbon monoxide between 1985 and 1994," said ASF executivedirector Bruce Landsberg. "But while accidents are rare, carbon monoxide can beinsidious and deadly."

A Piper Dakota crashed January 17 near Alton, New Hampshire, after the pilot andpassenger became incapacitated. The state medical examiner said both had suffered fromcarbon monoxide poisoning. NTSB investigators found a small "corrosion-type"hole in the aircraft muffler.

The cabin heating system in the Dakota – like most single-engine aircraft – providesheat by passing ambient air from the engine compartment through a shroud surrounding theexhaust muffler enroute to cabin heat outlets. A leak in the exhaust system could allowcarbon monoxide gas to enter the cabin.

Carbon monoxide – an odorless, tasteless, colorless gas – causes hypoxia when inhaled,reducing the blood’s ability to carry oxygen. That can lead to headache, drowsiness,dizziness, or even loss of consciousness and death.

"If you smell exhaust fumes in the cabin, you should immediately shut off theheater and open fresh air vents, even the storm window," said Landsberg. "If youever get a headache or become sleepy, dizzy or nauseous, suspect carbon monoxide and getfresh air immediately. Carbon monoxide can enter the cockpit without a detectable exhaustsmell."

Landsberg noted there are several different styles of carbon monoxide detectorsavailable for aircraft use. The Air Safety Foundation recommends installing a CO detectorand including it in the pilot’s instrument scan anytime cabin heat is in use.

The safety foundation noted that the inexpensive cardboard "dot" detectorsthat change color when exposed to CO gas must be replaced every 30 days. New technologydetectors with a longer useful life are now coming on the market.

"Most importantly, pilots should be sure their mechanics carefully check theentire exhaust system at each annual inspection," said Landsberg. "As aircraftage, regular inspection and maintenance become increasingly important."

The AOPA Air Safety Foundation is general aviation’s independent, non-profitorganization chartered in 1950 to improve general aviation safety. ASF producesvideotapes, pamphlets, newsletters, and other materials for continuing pilot education. Itconducts more than 300 safety seminars and Flight Instructor Refresher Clinics throughoutthe U.S. annually.