On 9th October 2003, a Cessna 172, suffered loss of power and made a forced landing after experiencing Piston Engine Induction Icing, over Toronto, Canada.
The following is an extract from the official report published by the Transportation Safety Board of Canada:
"At approximately 1300 eastern daylight time, the Toronto Airways Limited Cessna 172N aircraft…departed from the Toronto/Buttonville Municipal Airport on a sightseeing flight over Toronto, Ontario. The pilot and three passengers were on board. Before take-off, an engine ground run revealed no anomalies. The pilot applied full power for the take-off, climbed to an altitude of 2000 feet above sea level (1300 to 1400 feet above ground), levelled off, and selected the Toronto/City Centre Airport tower radio frequency. Shortly after that, the engine (Lycoming O-320-H2AD) began to lose power. The pilot informed the tower of the power loss and the intention to return to the Toronto/Buttonville Municipal Airport. Trying to regain power, the pilot ensured that full throttle was selected, checked the positions of the primer and magnetos, and switched fuel tanks. When these attempts were unsuccessful, the pilot selected the carburettor heat to the hot position, observed a further decrease in engine power, and reset the carburettor heat to the cold position. The engine was not producing enough power to maintain level flight and return to the airport, so the pilot searched for a suitable location for a forced landing. The aircraft was over a densely populated area, and the only suitable clearing was surrounded with trees and nearby buildings. The engine lost power on final approach. The pilot selected the flaps to the full-down position, overflew the clearing, and stalled the aircraft into the trees. The aircraft was substantially damaged and one passenger received minor injuries."
The report makes the following statement regarding the cause and contributing factors:
- "Ambient temperature and dew point conditions during the flight most likely resulted in carburettor icing, which caused the engine to lose power."
- "When the engine began to lose power, the pilot applied carburettor heat, but noted it resulted in a further decrease in engine power and selected the carburettor heat off. The heat was not on long enough to remove any ice."