# NTSB ANC21LA084: Piper PA-18-150, N371SC, Gustavus, AK, September 4, 2021 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 4 · Limited · Final report - Date: September 4, 2021, 10:00 local (18:00 UTC) - Place: Gustavus, AK - Coordinates: 58.406419, -136.98371 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=58.4064&lon=-136.9837&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 4 - Basic report with no Prelim publish - NTSB office: Alaska Regional Office - Parties: FAA - NTSB case key (mKey): 103829 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC21LA084 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/103829/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=103829 - Page: https://openairdocs.org/ntsb/ANC21LA084 ## Probable cause The pilot’s failure to maintain directional control during an off-airport beach landing. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Piper PA-18-150, 98 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=7101828), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Piper PA-18-150, 160 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7101828), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Wind: crosswind](https://openairdocs.org/ntsb-findings/03034040): Environmental issues › Conditions/weather/phenomena · Ability to respond/compensate; cases with it: [Piper PA-18-150, 13 cases](https://openairdocs.org/ntsb-findings/03034040/cases.md?model=7101828), [All aircraft, 1,008 cases](https://openairdocs.org/ntsb-findings/03034040/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Landing: Loss of control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Piper PA-18-150, 109 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=7101828), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) - [Landing: Landing gear collapse](https://openairdocs.org/ntsb-events/094); cases with it: [Piper PA-18-150, 16 cases](https://openairdocs.org/ntsb-events/094/sequence.md?model=7101828), [All aircraft, 1,787 cases](https://openairdocs.org/ntsb-events/094/sequence.md) ## Analysis The pilot of the tailwheel-equipped airplane reported that he was landing off-airport, on a sloped tidal beach, with a crosswind. During the landing the airplane veered left, and he attempted to correct to no avail. Subsequently, the right main landing gear collapsed, and the airplane came to rest about 90° to the left of the intended landing path. The airplane sustained substantial damage to the right wing. The pilot reported no preimpact mechanical failures or malfunctions with the airplane that would have precluded normal operation. ## Aircraft - Registration: [N371SC](https://openairdocs.org/aircraft/N371SC), registered now, S/N 18-8914, built 1970 (OpenAirDocs) - Reported make and model: PIPER PA-18-150 - Registry model: [Piper PA-18-150](https://openairdocs.org/model/piper-pa-18-150) (registry code 7101828) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18-8914 - Year built: 1970 - Airframe hours: 3125.2 - Engines: LYCOMING O-360-A4M 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 5, 2021 - Departed: PAOH, Hoona, AK - Equipment: Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 65; injuries: none; airline transport; airplane ratings: multi-engine land, single-engine land, single-engine sea; instrument ratings: airplane; medical: class 3, with waivers/limitations; last flight review April 19, 2020; seat: front; restraint: 5-point; flight hours: 9,126 total, 590 in this make and model, 8,223 as pilot in command, 30 in the last 90 days, 14 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 310° at 7 knots - Visibility: 10 statute miles - Lowest ceiling: 400 ft overcast - Temperature: 54 °F, dew point 52 °F - Altimeter: 29.53 inHg - Observed at: PAGS, 40 nm away - METAR: PAGS 041756Z AUTO 31007KT 10SM OVC004 12/11 A2953 RMK AO2 SLP998 60004 T01170111 10122 20117 56023 ## 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 20210904016519A](https://openairdocs.org/incident/20210904016519A), Sep 4, 2021: Piper PA-18-150, Elfin Cove, AK, Substantial damage. Aircraft landed on beach in boussole bay, from nw to se direction, with a left crosswind (land breeze). Combination of uphill turning tendency after touchdown… ## Docket (2 files) The files NTSB released with the investigation on March 21, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=103829. 3.3 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 10 pages, 3.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12730201&FileExtension=pdf&FileName=6120_Redacted-Rel.pdf - Accident pictures (item 2, PDF, 2 pages, 121 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=12730353&FileExtension=pdf&FileName=Accident%20Pictures-Rel.pdf 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.