# NTSB ANC07LA015: Piper PA-18, N237WT, Tyonek, AK, January 13, 2007 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 13, 2007, 18:00 local (22:00 UTC) - Place: Tyonek, AK - Coordinates: 61.229999, -152.070831 - Nearby events: https://openairdocs.org/map.md?lat=61.2300&lon=-152.0708&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report July 25, 2007 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: Anchorage FSDO-03 - NTSB case key (mKey): 65535 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC07LA015 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/65535/pdf - Page: https://openairdocs.org/ntsb/ANC07LA015 ## Probable cause The pilot's selection of unsuitable terrain for takeoff, which resulted in a loss of directional control on the ground, and the wing impacting the snow-covered terrain. A factor associated with the accident was the snow-covered terrain. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Loss of control - on ground/water, takeoff - roll/run - unsuitable terrain or takeoff/landing/taxi area - selected, pilot in command (cause) - On ground/water encounter with terrain/water, takeoff - roll/run - terrain condition - snow covered (contributing factor) ## Analysis The airplane was being operated by the private pilot as a visual flight rules (VFR) personal cross-country flight under Title 14, CFR Part 91. The pilot said he landed the ski-equipped airplane in a snow-covered meadow. He said the snow conditions were not what he had expected, and prior to takeoff, he had to dig the airplane out, and pack down an area around the airplane with his snowshoes. He said he packed down a takeoff area, and removed as much gear from the airplane as possible to lighten the takeoff load. During the takeoff roll, the pilot said the airplane veered off the packed area, burying the right ski and wing in the snow. The mechanic who examined the airplane said both the fore and aft main spars in the right wing would have to be replaced. The airplane was not examined by the NTSB. ## Factual narrative On January 13, 2007, about 1800 Alaska standard time, a ski-equipped, Piper PA-18 airplane, N237WT, sustained substantial damage following a loss of directional control during takeoff, about 28 miles west-northwest of Tyonek, Alaska. The airplane was being operated by the pilot as a visual flight rules (VFR) personal cross-country flight under Title 14, CFR Part 91, when the accident occurred. The solo, private certificated pilot was not injured. Visual meteorological conditions prevailed, and no flight plan was filed. During a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) on January 15, the pilot said he had landed the ski-equipped airplane in a snow-covered meadow. He said prior to landing he had set down tracks, and determined the area was suitable for landing. The pilot said after landing, the airplane sank into the snow, and came to a abrupt stop. He said the snow conditions were not what he had expected. He dug the airplane out, and packed down an area around the airplane with his snowshoes. He indicated he packed down a takeoff area, and removed as much gear from the airplane as possible to lighten the takeoff load. During the takeoff roll the pilot said the airplane veered off the packed area, burying the right ski and wing in the snow. After he dug the airplane out, he saw the wing and propeller were damaged. The airplane was taken by helicopter to its home airport, and surveyed by a mechanic. During a telephone conversation with the NTSB IIC, the mechanic said both the fore and aft main spars in the right wing would have to be replaced. The pilot did not submit a Pilot/Operator Aircraft Accident/Incident Report. The airplane was not examined by the NTSB. ## Aircraft - Registration: [N237WT](https://openairdocs.org/aircraft/N237WT), registered now, S/N 18 237 (OpenAirDocs) - Reported make and model: Piper PA-18 - Registry model: [Piper PA-18](https://openairdocs.org/model/piper-pa-18) (registry code 7101802) (OpenAirDocs) - Registry engine: [Lycoming 0-290 series](https://openairdocs.org/engine/lycoming-0-290-series) (registry code 41506, 4 cycle) (OpenAirDocs) - Category: Airplane - Engines: Lycoming O-290 reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Scott Gage - Departed: Tyonek, AK - Destination: MRI, Merrill Field, AK ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 36; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations ## Weather - Conditions: Visual (VMC) - Wind: 0 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 32 °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 20070113000859A](https://openairdocs.org/incident/20070113000859A), Jan 13, 2007: Piper PA18, Tyonek, AK, Substantial damage. (-23) The pilot, while conducting animal trapping activities, landed in a meadow frequently used by him for such. Shortly after landing, the aircraft became… ## Other investigations on N237WT (1) 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. - [NTSB ANC06CA013](https://openairdocs.org/ntsb/ANC06CA013), Dec 21, 2005: Piper PA-18 (N237WT), Skwentna, AK, substantial damage. Probable cause: The pilot's selection of an unsuitable landing area, which resulted in an on ground collision with trees during the landing roll. Factors associated with the accident were the icy and snow-covered… 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.