# NTSB ANC97LA006: Piper PA-22/20, N7431D, Kasilof, AK, October 26, 1996 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: October 26, 1996, 14:00 local (22:00 UTC) - Place: Kasilof, AK - Coordinates: 60.279666, -151.259445 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=60.2797&lon=-151.2594&mi=10 - Phase of flight: [Approach](https://openairdocs.org/ntsb-phases/500) (OpenAirDocs' grouping) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report March 31, 1998 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - NTSB case key (mKey): 2951 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC97LA006 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/2951/pdf - Page: https://openairdocs.org/ntsb/ANC97LA006 ## Probable cause the pilot's misjudgment of distance and altitude on final approach to land, which resulted in an undershoot and collision with a dirt bank before reaching the proper touchdown point. A factor related to the accident was: the proximity of the frozen dirt bank at the approach end of the intended point of landing. ## Sequence of events In NTSB's coding before 2008 (https://www.ntsb.gov/GILS/Documents/codman.pdf). - Undershoot, approach - vfr pattern - final approach - distance/altitude - misjudged, pilot in command (cause) - In flight collision with terrain/water, landing - flare/touchdown - terrain condition - dirt bank/rising embankment (contributing factor) ## Analysis The pilot was conducting touch-and-go operations on a frozen lake adjacent to his property. A small frozen mound of dirt was located at the approach end of the lake. The pilot indicated that he was concerned about stopping on the frozen surface of the lake, and his approach path to the lake was a little low. The right main landing gear struck the mound of dirt before touchdown and was folded back against the fuselage. The airplane then contacted the surface of the lake and received damage to the right main landing gear, propeller, and the spar and outboard ribs of the right wing. ## Factual narrative On October 26, 1996, about 1400 Alaska daylight time, a wheel equipped Piper PA-22/20, N7431D, collided with terrain at a frozen lake near Kasilof, Alaska. The airplane was being operated as a visual flight rules (VFR) local area personal flight when the accident occurred. The airplane, registered to and operated by the pilot sustained substantial damage. The certificated private pilot, the sole occupant, was not injured. Visual meteorological conditions prevailed. On October 31, 1996, at 0900, the pilot reported in a telephone conversation with the National Transportation Safety Board (NTSB) investigator-in-charge (IIC) that he was conducting touch and go operations on a frozen lake adjacent to his property. The lake is oriented on a north/south direction and he was landing toward the north. It is about 1,200 feet long and about 40 feet wide. A small frozen mound of dirt is located at the approach end of the lake. The pilot indicated that he was concerned about stopping on the frozen surface of the lake and his approach path to the lake was a little low. The right main landing gear struck the mound of dirt before touchdown and was folded back against the fuselage. The airplane then contacted the surface of the lake and received damage to the right main landing gear, propeller, and the spar and outboard ribs of the right wing. ## Aircraft - Registration: [N7431D](https://openairdocs.org/aircraft/N7431D), registered now, S/N 22-5190, built 1957 (OpenAirDocs) - Reported make and model: Piper PA-22/20 - Registry model: [Piper PA-22-150](https://openairdocs.org/model/piper-pa-22-150) (registry code 7102210) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 22-5190 - Airframe hours: 2013 - Engines: Lycoming O-320 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Registered owner: Tommy J. Hudson - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 21, 1996, 29 hours before ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 44; private; airplane ratings: single-engine land; medical: class 3, valid medical--no waivers/lim.; seat: left; flight hours: 173 total, 106 in this make and model, 129 as pilot in command, 45 in the last 90 days, 10 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 10° at 5 knots - Visibility: 70 statute miles - Lowest ceiling: none - Temperature: 19 °F, dew point 7 °F - Altimeter: 29.00 inHg ## 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 19961026035669A](https://openairdocs.org/incident/19961026035669A), Oct 26, 1996: Piper PA22150, Kasilof, AK, Substantial damage. Practice landings on frozen lake. Right main folded back by dirt berm on final. Landed on lake on main and nose. ## Other investigations on N7431D (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 ANC68F0012](https://openairdocs.org/ntsb/ANC68F0012), May 12, 1967: Piper PA-22 (N7431D), Anchorage, AK, substantial damage 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.