# NTSB ANC97LA053: Piper PA-12, N92793, Nikiski, AK, April 18, 1997 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: April 18, 1997, 14:00 local (22:00 UTC) - Place: Nikiski, AK - Location: 60.7253° N, 151.3022° W: Placed by OpenAirDocs at MCGAHAN INDUSTRIAL AIRPARK (AK73), within about a mile (OpenAirDocs) - Nearby events: https://openairdocs.org/map.md?lat=60.7253&lon=-151.3022&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 29, 1998 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 2986 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC97LA053 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/2986/pdf - Page: https://openairdocs.org/ntsb/ANC97LA053 ## Probable cause the pilot's improper installation of the landing gear wheel. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Airframe/component/system failure/malfunction, takeoff - landing gear,wheel - not secured (cause) - maintenance,installation - improper, pilot in command (cause) - landing gear,wheel - separation - Main gear collapsed, landing - flare/touchdown - landing gear,main gear attachment - overload ## Analysis The solo student pilot was practicing takeoff and landings in his airplane. The airplane had previously been equipped with fixed skis. The pilot removed the skis, and replaced them with large tundra tires. The pilot landed at an intermediate airport, and attempted to turn the airplane to the left in preparation for departure. The airplane was hard to turn, and the pilot got out of the airplane and physically moved the tail around to position the airplane for takeoff. After liftoff, the pilot noticed the left wheel and tire fall off the axle. He continued to his destination and landed on a gravel runway at a private airstrip. After touchdown, the right main gear collapsed, folding under the wheel. The airplane received damage to the main landing gear, the right wing spar, and right wing lift struts. An inspection of the airplane revealed the left wheel axle retaining nut was missing. ## Factual narrative On April 18, 1997, at 1400 Alaska daylight time, a tundra tire equipped Piper PA-12, N92793, crashed during landing at Nikiski, Alaska. The airplane was being operated as a visual flight rules (VFR) local area instructional flight when the accident occurred. The airplane, registered to and operated by the pilot, sustained substantial damage. The solo student pilot was not injured. Visual meteorological conditions prevailed. The flight originated at Kasilof, Alaska, at 1330. A Federal Aviation Administration (FAA) airworthiness inspector, Anchorage Flight Standards District Office (FSDO), reported the airplane had previously been equipped with fixed skis. The pilot removed the skis, and replaced them with large tundra tires. The pilot was practicing takeoff and landings. He landed at Kasilof, and attempted to turn the airplane to the left in preparation for departure. The airplane was hard to turn, and the pilot got out of the airplane, and physically moved the tail around to position the airplane for takeoff. After liftoff, the pilot noticed the left wheel and tire fall off the axle. The pilot continued to his destination and landed on a private airstrip, known as McGahan Industrial Airpark, located about 1 mile southwest of Nikiski. The pilot touched down on the gravel runway, and the right main gear collapsed, folding under the wheel. The airplane received damage to the main landing gear, the right wing spar, and right wing lift struts. An inspection of the airplane by the FAA revealed the left wheel axle retaining nut was missing. ## Aircraft - Registration: [N92793](https://openairdocs.org/aircraft/N92793), registered now, S/N 12-239, built 1946 (OpenAirDocs) - Reported make and model: Piper PA-12 - Registry model: [Piper PA-12](https://openairdocs.org/model/piper-pa-12) (registry code 7101202) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 12-239 - Airframe hours: 4500 - Engines: Lycoming O-320-B3B 160 horsepower reciprocating - Damage: Substantial damage - Flight: Instructional, Part 91 - Registered owner: James R. Heazlett - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 17, 1996, 140 hours before - Departed: 5KS, KASILOF, AK - Destination: AK73 - Airport: AK73, Mcgahan Industrial, runway 6, 4,000 × 150 ft, gravel ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 40; student; medical: class 3, valid medical--no waivers/lim.; seat: front ## Weather - Conditions: Visual (VMC), Day - Wind: 350° at 5 knots - Visibility: 30 statute miles - Lowest ceiling: none - Temperature: 55 °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 19970418006249A](https://openairdocs.org/incident/19970418006249A), Apr 18, 1997: Piper PA12, Nikishka, AK, Substantial damage. Changed gear from skis to tundra tires. On takeoff wheel fell off. Continues to home base. Gear wing spar damaged. ## Other investigations on N92793 (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 ANC21LA039](https://openairdocs.org/ntsb/ANC21LA039), May 12, 2021: Piper PA-12 (N92793), Kenai, AK, substantial damage. Probable cause: The pilot's excessive application of the airplane’s wheel brakes while landing, which resulted in a nose over. 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.