Casualties unknown

2004-09-15: Cessna 140 (N1629V) — North Pole, AK

North Pole, AK, US

On September 15, 2004, a Cessna 140 (registration N1629V) was involved in an aviation accident near North Pole, AK. Investigators recorded the probable cause as: The pilot's failure to use carburetor heat during takeoff/initial climb, which resulted in a total loss of engine power, and an in-flight collision with trees. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.

Sourcesthe U.S. National Transportation Safety Board (NTSB) historical archivePrimary reportUpdated 1781061362Data APIEditorial standards

During initial climb from a private airstrip, the engine ran rough and lost power. The pilot did not apply carburetor heat, and the aircraft impacted trees. Post-accident engine test revealed no mechanical anomalies.

Accident Overview

A private pilot was conducting a flight from a private airstrip. During initial climb, the engine began running roughly, lost power, and subsequently ceased operation. The pilot reported checking the throttle and fuel selector when the roughness started but did not apply carburetor heat, as he was aware that doing so would reduce engine rpm. After the engine lost all power, the pilot determined that he did not have sufficient altitude to turn back to the runway or reach a suitable landing area. He elected to continue straight ahead, and the airplane flew into trees.

Weather Conditions

The nearest official weather reporting station, located approximately 15 miles northwest of the accident site, reported at 1755: visibility 4 miles in light rain, temperature and dew point both 36 degrees Fahrenheit, and a ceiling of 400 feet broken, 1000 feet overcast. At the accident site, the pilot estimated the ceiling at 600 feet, visibility at 3 miles, and both temperature and dew point at 36 degrees Fahrenheit.

Carburetor Icing Considerations

A carburetor icing probability chart, included in the accident docket, indicates that with a temperature and dew point of 36 degrees Fahrenheit each, there is potential for serious carburetor icing at cruise and climb power settings. Additionally, FAA Advisory Circular 61-23C, Chapter 2, Carburetor Icing, states that when temperatures are between 20°F and 70°F with visible moisture or high humidity, pilots should be alert for carburetor ice. It further notes that an engine is particularly susceptible to carburetor icing during low or closed throttle settings.

Post-Accident Examination

The engine was recovered to a maintenance facility and placed on an engine test stand. The engine and propeller did not require any repair as a result of the accident. The engine was started and run through various power settings, and no mechanical anomalies were found. The pilot reported that there were no known mechanical issues with the airplane prior to the flight.

Investigation report by the U.S. National Transportation Safety Board (NTSB) historical archive. Original record: https://carol.ntsb.gov/event/20040917X01449. This page is a structured re-presentation; facts and quotes are in the National Transportation Safety Board (NTSB), United States.