# NTSB ANC22LA020: Piper PA-18-135, N99640, Wasilla, AK, February 27, 2022

- Type: NTSB accident investigation
- Classification: Accident · Minor injuries · Class 3 · Limited · Final report
- Date: February 27, 2022, 12:32 local (21:32 UTC)
- Place: Wasilla, AK
- Coordinates: 61.639338, -149.28758
- Nearby events: https://openairdocs.org/map.md?lat=61.6393&lon=-149.2876&mi=10
- Phase of flight: [Unknown](https://openairdocs.org/ntsb-phases/990) (OpenAirDocs' grouping)
- Defining event: [Unknown: Unknown or undetermined](https://openairdocs.org/ntsb-events/000)
- Highest injury: Minor injuries
- Injuries: 1 minor
- Status: Completed
- Report: Approved by Office Director
- Investigation class: Class 3
- NTSB office: Alaska Regional Office
- Parties: FAA
- NTSB case key (mKey): 104713
- NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC22LA020
- NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/104713/pdf
- NTSB docket: https://data.ntsb.gov/Docket?ProjectID=104713
- Page: https://openairdocs.org/ntsb/ANC22LA020

## Probable cause

A partial loss of engine power for undetermined reasons.

## Findings

NTSB's coded findings; those marked are part of the probable cause.

- [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Piper PA-18-135, 2 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=7101820), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md)

## Sequence of events

The events NTSB coded, in order, by phase of flight. The defining event best describes what happened.

- [Takeoff: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342); cases with it: [Piper PA-18-135, 3 cases](https://openairdocs.org/ntsb-events/342/sequence.md?model=7101820), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md)
- [Unknown: Unknown or undetermined](https://openairdocs.org/ntsb-events/000) (defining event); cases with it: [Piper PA-18-135, 1 case](https://openairdocs.org/ntsb-events/000/sequence.md?model=7101820), [All aircraft, 1,703 cases](https://openairdocs.org/ntsb-events/000/sequence.md)

## Analysis

The noncertificated pilot stated that, shortly after takeoff, the engine began to lose power, run roughly, and shake violently. He applied carburetor heat and selected the left fuel tank, then the right fuel tank before selecting both fuel tanks with no change noted. He reduced engine power to control the airplane shaking and conducted an emergency landing. During the emergency landing, the airplane sustained substantial damage to the wings and fuselage. A postaccident examination revealed that the fuel selector was improperly labeled. However, the examination of the engine, accessories, and the other fuel system components revealed no mechanical malfunctions or anomalies that would have precluded normal operation. As a result, the reason for the partial loss of engine power and the engine’s rough operation could not be determined.

## Factual narrative

On February 27, 2022, about 1232 Alaska standard time, a Piper P-18 airplane, N99640, sustained substantial damage when it was involved in an accident near Wolf Lake Airport (4AK6), Wasilla, Alaska. The pilot sustained minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The noncertificated pilot stated that, after departure from 4AK6 and while the airplane was about 100 ft above ground level, the engine began to lose power, run roughly, and shake violently. To restore engine power, he applied carburetor heat and selected the left fuel tank and then the right fuel tank before selecting both tanks, but those actions did not restore power. He reduced engine power to control the airplane shaking and conducted an emergency landing. During the emergency landing, the airplane impacted a burn barrel and came to rest against a hangar, which resulted in substantial damage to the wings and fuselage. A postaccident examination revealed that the Maule-type fuel selector had been mislabeled. Specifically, the position labeled “both” was for the right tank, the position labeled “left” was the “off” position, the position labeled “right” was for the left tank, and the position labeled “off” was for both tanks. The examination of the engine, its accessories, and the other fuel system components revealed no mechanical malfunctions or anomalies that would have precluded normal operation.

## Aircraft

- Registration: [N99640](https://openairdocs.org/deregistered/N99640-2023-06-17), registration cancelled 2023-06-17, S/N 54-2642 (OpenAirDocs)
- Reported make and model: PIPER PA-18-135
- Registry model: [Piper PA-18-135](https://openairdocs.org/model/piper-pa-18-135) (registry code 7101820) (OpenAirDocs)
- Category: Airplane
- Serial number: 54-2642
- Damage: Substantial damage
- Flight: Personal, Part 91
- Registered owner: B-407 LLC
- Airworthiness certificate: Unknown
- Airport: 4AK6, Wolf Lake Airport, runway 26, 3,800 × 40 ft, asphalt
- Equipment: Handheld GPS

## Flight crew

As NTSB recorded them. NTSB leaves out names.

- Pilot; age 60; injuries: minor; seat: front

## Weather

- Conditions: Visual (VMC), Day
- Wind: calm
- Visibility: 10 statute miles
- Lowest ceiling: 20,000 ft broken
- Temperature: 36 °F, dew point 27 °F
- Altimeter: 29.54 inHg
- Observed at: PAAQ, 6 nm away
- METAR: PAAQ 272153Z 00000KT 10SM FEW050 BKN200 02/M03 A2954 RMK AO2 SLP006 T00171028

## 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 20220227002929A](https://openairdocs.org/incident/20220227002929A), Feb 27, 2022: Piper PA-18-135, Wasilla, AK, Substantial damage. 33. Person acting as pilot (not certificated) was conducting the initial flight after his extensive repairs and reassembly of the aircraft. The aircraft had…

## Other investigations on N99640 (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 ANC21LA060](https://openairdocs.org/ntsb/ANC21LA060), Jul 16, 2021: Piper PA-18-135 (N99640), Skwentna, AK, substantial damage. Probable cause: The pilot’s use of excessive braking which resulted in a nose-over.

## Docket (3 files)

The files NTSB released with the investigation on August 23, 2023, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=104713. 2.4 MB in all.

- FAA inspector statement (item 1, PDF, 3 pages, 144 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13588605&FileExtension=pdf&FileName=FAA%20Inspector%20Statement_Redacted-Rel.pdf
- Wreckage examination summary (item 2, PDF, 5 pages, 757 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13588246&FileExtension=pdf&FileName=Examination%20Summary%20ANC22LA020-Rel.pdf
- Photos (item 3, PDF, 2 pages, 1.5 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13573579&FileExtension=pdf&FileName=Photo%20Array-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.

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