# NTSB ANC96LA024: Cessna 180, N4762B, Tanana, AK, December 30, 1995 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: December 30, 1995, 11:00 local (15:00 UTC) - Place: Tanana, AK - Coordinates: 65.180496, -152.069656 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=65.1805&lon=-152.0697&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report April 18, 1996 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 2797 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC96LA024 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/2797/pdf - Page: https://openairdocs.org/ntsb/ANC96LA024 ## Probable cause The icing of the induction/intake screen and the pilot's improper planning/decision by electing to takeoff into suspended snow and ice crystals. ## Analysis The pilot was attempting to takeoff and return to Fairbanks, Alaska. He had to taxi up hill for a distance of 1,500 feet. He used carburetor heat during his taxi. When he turned the airplane around to line up for takeoff, he noticed fine snow and ice crystals suspended in the air over his intended takeoff area. The pilot turned the carburetor heat off, applied full power, and made the takeoff. When the airplane reached approximately 15 feet above ground level, the engine lost power. The pilot applied carburetor heat and some power was restored. The pilot stated he had to lower the nose to maintain airspeed and the airplane crashed into the trees. The pilot stated he thought the intake screen had become iced over during the taxi and takeoff. ## Factual narrative On December 30, 1995, at 1100 Alaska standard time, a wheel equipped Cessna 180 airplane, N4762B, registered to and operated by the pilot, lost engine power and crashed into trees after takeoff from an unimproved takeoff area on the Cosna River located 40 miles southeast of Tanana, Alaska. The personal flight, operating under 14 CFR Part 91, was departing the Cosna River and the destination was Fairbanks, Alaska. No flight plan was filed and visual meteorological conditions prevailed. The commercial certificated pilot, the sole occupant, was not injured and the airplane received substantial damage. According to the pilot's statement attached to the NTSB Form 6120.1/2, he had to taxi the airplane a distance of 1,500 feet uphill to reach the takeoff area. He taxied with the carburetor heat applied. He said that during his taxi a lot of fine snow and ice crystals were blown up and remained suspended over the takeoff area. After performing an engine runup, he started his takeoff. The airplane reached an altitude of approximately 15 feet when the engine began to produce only partial engine power. The pilot stated he applied carburetor heat again and some power was restored. He had to lower the airplane's nose to maintain flying speed and the airplane crashed into trees. During an interview between the pilot and a FAA Flight Standards Inspector, the pilot stated that he thought the air intake screen had become clogged with snow and ice during his taxi to the takeoff area. Subsequent examination of the engine and airplane showed no mechanical defect of the engine or associated airplane systems. According to information provided in the Cessna 180 owner's manual, under section 3 titled: Operating Details, "The carburetor heat knob should be pushed full in (cold, off) during all ground operations unless heat is absolutely necessary for smooth engine operation. When the knob is pulled out to the heat position, air entering the engine is not filtered." There is no information in the owner's manual concerning the effect of snow and ice on the intake/induction screen during taxi and takeoff. A review of information on winter flying and winter operations, provided by the FAA, showed no discussion concerning taxiing through blowing snow, suspended snow, or ice crystal, and the effect on induction intake screen icing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of engine power(partial) - nonmechanical, takeoff - initial climb - induction air control,air filter/screen - ice (cause) - planning/decision - improper, pilot in command (cause) - Forced landing, emergency landing after takeoff - In flight collision with object, descent - emergency - object - tree(s) ## Aircraft - Registration: [N4762B](https://openairdocs.org/aircraft/N4762B), registered now, S/N 31660, built 1955 (OpenAirDocs) - Reported make and model: CESSNA 180 - Registry model: [Cessna 180](https://openairdocs.org/model/cessna-180) (registry code 2072602) (OpenAirDocs) - Registry engine: [Continental O-470R](https://openairdocs.org/engine/continental-o-470r) (registry code 17071, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 31660 - Airframe hours: 2680 - Engines: CONTINENTAL O-470-R 230 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Charles R. Deer - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 15, 1995, 117 hours before - Destination: FAI, FAIRBANKS, AK ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 58; commercial; airplane ratings: single-engine sea, multi-engine land, single-engine land; instrument ratings: airplane; medical: class 3, expired; seat: left; flight hours: 3,229 total, 1,500 in this make and model, 3,100 as pilot in command, 29 in the last 90 days, 6 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Visibility: 20 statute miles - Lowest ceiling: 2,000 ft overcast - Temperature: -0 °F ## FAA reports on this event (1) The FAA's own accident and incident reports, matched to the aircraft by N-number and date (OpenAirDocs). - [Accident 19951230043569A](https://openairdocs.org/incident/19951230043569A), Dec 30, 1995: Cessna 180, Tanana, AK, Substantial damage. Crashed into trees on takeoff. Had taxied carb heat on. Unfiltered air open to dirt and ice on filter reduced power From the NTSB's public API. Aircraft are matched to registry aircraft by N-number and event date, checked against the reported serial number, make and model; the registry's history has gaps, so older matches can be wrong. Compare the reported make and model. --- OpenAirDocs.org is an independent research project of [Contrail Labs](https://contraillabs.com/). It is not affiliated with the FAA or the NTSB. Source documents are U.S. government works in the public domain.