# NTSB GAA19CA551: Piper PA 12, N4315M, Healy, AK, September 15, 2019 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: September 15, 2019, 12:15 local (20:15 UTC) - Place: Healy, AK - Coordinates: 63.95111, -144.671661 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=63.9511&lon=-144.6717&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report March 17, 2020 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: FAA - NTSB case key (mKey): 100278 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA19CA551 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/100278/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=100278 - Page: https://openairdocs.org/ntsb/GAA19CA551 ## Probable cause The pilot's exceedance of the airplane's critical angle of attack while taking off from water in shifting wind conditions. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Performance/control parameters: angle of attack](https://openairdocs.org/ntsb-findings/01062042): Aircraft › Aircraft oper/perf/capability · Capability exceeded (probable cause); cases with it: [Piper PA-12, 7 cases](https://openairdocs.org/ntsb-findings/01062042/cases.md?model=7101202), [All aircraft, 990 cases](https://openairdocs.org/ntsb-findings/01062042/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-12, 51 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7101202), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Wind: sudden wind shift](https://openairdocs.org/ntsb-findings/03034010): Environmental issues › Conditions/weather/phenomena · Effect on operation (probable cause); cases with it: [Piper PA-12, 5 cases](https://openairdocs.org/ntsb-findings/03034010/cases.md?model=7101202), [All aircraft, 114 cases](https://openairdocs.org/ntsb-findings/03034010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Other weather encounter](https://openairdocs.org/ntsb-events/400); cases with it: [Piper PA-12, 7 cases](https://openairdocs.org/ntsb-events/400/sequence.md?model=7101202), [All aircraft, 1,127 cases](https://openairdocs.org/ntsb-events/400/sequence.md) - [Takeoff: Aerodynamic stall/spin](https://openairdocs.org/ntsb-events/241) (defining event); cases with it: [Piper PA-12, 6 cases](https://openairdocs.org/ntsb-events/241/sequence.md?model=7101202), [All aircraft, 1,529 cases](https://openairdocs.org/ntsb-events/241/sequence.md) - [Takeoff: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Piper PA-12, 42 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7101202), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Takeoff: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Piper PA-12, 36 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=7101202), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis The pilot reported that, while taking off from water to the east, the wind shifted from the east to the south. The airplane became airborne and then aerodynamically stalled, and the left wing impacted the water. The airplane came to rest inverted in the water. The airplane sustained substantial damage to the fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. ## Factual narrative The pilot of the float-equipped airplane reported that, during a water takeoff to the east, the wind shifted from the east to the south. The airplane became airborne, aerodynamically stalled, and the left wing impacted the water. The airplane came to rest inverted in the water. The airplane sustained substantial damage to the fuselage. The pilot reported that there were no preaccident mechanical failures or malfunctions with the airplane that would have precluded normal operation. The pilot reported that the wind was from 115° at 30 knots, gusting to 30 knots. ## Aircraft - Registration: [N4315M](https://openairdocs.org/aircraft/N4315M), registered now, S/N 12-3248, built 1947 (OpenAirDocs) - Reported make and model: Piper PA 12 (No Series) - Registry model: [Piper PA-12](https://openairdocs.org/model/piper-pa-12) (registry code 7101202) (OpenAirDocs) - Registry engine: [Lycoming 0-235 series](https://openairdocs.org/engine/lycoming-0-235-series) (registry code 41505, 4 cycle) (OpenAirDocs) - Category: Airplane - Serial number: 12-3248 - Year built: 1947 - Airframe hours: 1085.6 - Engines: Lycoming O-320-A2B 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, May 25, 2019 - Departed: Healy, AK - Destination: FAI, Fairbanks, AK - Equipment: Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 60; injuries: none; private; airplane ratings: single-engine land, single-engine sea; medical: class 3, with waivers/limitations; last flight review September 10, 2016; seat: front; flight hours: 600 total, 150 in this make and model, 500 as pilot in command, 4 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: 110° at 16 knots - Visibility: 10 statute miles - Temperature: 54 °F, dew point 39 °F - Altimeter: 29.61 inHg - Observed at: PABI, 28 nm away ## 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 20190915016899A](https://openairdocs.org/incident/20190915016899A), Sep 15, 2019: Piper PA-12, Healy Lake, AK, Substantial damage. In pilots words: ?after assessing local weather, deemed safe to operate. Taxi with prevailing wind from east. Took off into prevailing winds. Wind shifted… ## Docket (3 files) The files NTSB released with the investigation on November 26, 2019, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=100278. 1.3 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 1.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40478390&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Record of Conversation - FAA Inspector (item 2, .PDF, 67 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40478391&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20FAA%20Inspector-Master.PDF - Accident Photo (item 3, .PDF, 1 photo, 203 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40478392&FileExtension=.PDF&FileName=Accident%20Photo-Master.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.