# NTSB ANC11CA013: Piper PA-18, N623MP, Sterling, AK, February 23, 2011 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: February 23, 2011, 17:15 local (21:15 UTC) - Place: Sterling, AK - Coordinates: 60.553054, -150.838882 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=60.5531&lon=-150.8389&mi=10 - Phase of flight: [Landing](https://openairdocs.org/ntsb-phases/550) (OpenAirDocs' grouping) - Defining event: [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report June 20, 2011 - Report: Approved by Office Director - NTSB office: Alaska Regional Office - Parties: FAA FSDO - NTSB case key (mKey): 78431 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ANC11CA013 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/78431/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=78431 - Page: https://openairdocs.org/ntsb/ANC11CA013 ## Probable cause The airplane owner improper fabrication of a fuel line, and subsequent inadequate inspection by an aviation mechanic, resulting in a loss of engine power. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Misc hardware: hoses and tubes](https://openairdocs.org/ntsb-findings/01071410): Aircraft › Fluids/misc hardware · Inadequate inspection (probable cause); cases with it: [Piper PA-18, 1 case](https://openairdocs.org/ntsb-findings/01071410/cases.md?model=7101802), [All aircraft, 40 cases](https://openairdocs.org/ntsb-findings/01071410/cases.md) - [Maintenance: fabrication](https://openairdocs.org/ntsb-findings/02062025): Personnel issues › Task performance · Owner/builder (probable cause); cases with it: [Piper PA-18, 1 case](https://openairdocs.org/ntsb-findings/02062025/cases.md?model=7101802), [All aircraft, 30 cases](https://openairdocs.org/ntsb-findings/02062025/cases.md) - [Engine fuel and control: fuel distribution](https://openairdocs.org/ntsb-findings/01057310): Aircraft › Aircraft power plant · Damaged/degraded (probable cause); cases with it: [Piper PA-18, 1 case](https://openairdocs.org/ntsb-findings/01057310/cases.md?model=7101802), [All aircraft, 55 cases](https://openairdocs.org/ntsb-findings/01057310/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Piper PA-18, 2 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=7101802), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Piper PA-18, 3 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=7101802), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096) (defining event); cases with it: [Piper PA-18, 16 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=7101802), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis According to the pilot, the accident flight was the first flight after a major rebuild of the airplane. After completing ground runs on the engine, he and a passenger departed for a test flight. During the initial climb, approximately 600 feet above the ground, the engine lost power. He elected to land in a snow-covered field and during the landing the airplane nosed over. Substantial damage was sustained to both the front and rear lift struts on the right wing. A postaccident inspection of the fuel system by the pilot revealed a flap of rubber inside a flexible fuel hose that was of significant size to restrict fuel flow to the engine. The fuel hose was fabricated by the airplane owner, under the supervision of the mechanic. The fuel hose which was fabricated out of flexible automotive hydraulic line was not an approved aircraft-grade fuel hose. ## Factual narrative According to the pilot's statement, the accident flight was the first flight after a major rebuild of the airplane. After completing ground runs on the engine, the pilot and passenger departed the airport for a test flight. During the initial climb, approximately 600 feet above the ground, the engine lost power. The pilot elected to land in a snow covered field, and during the landing the airplane nosed over. Substantial damage was sustained to both the front and rear lift struts on the right wing. A postaccident inspection of the fuel system by the pilot, who is also the mechanic that oversaw the rebuild of the airplane, revealed a flap of rubber inside a flexible fuel hose that was of significant size to restrict fuel flow to the engine. The fuel hose was fabricated by the airplane owner, under the supervision of the mechanic. The fuel hose was fabricated out of flexible automotive hydraulic line, not approved aircraft-grade fuel hose. ## Aircraft - Registration: [N623MP](https://openairdocs.org/aircraft/N623MP), registered now, S/N 188090, built 1964 (OpenAirDocs) - Reported make and model: PIPER PA-18 - Registry model: [Piper PA-18](https://openairdocs.org/model/piper-pa-18) (registry code 7101802) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 188090 - Engines: LYCOMING O-320 SERIES 150 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Johnson Johnny L - Registered owner: Johnson Johnny L - Airworthiness certificate: Standard, Normal - Departed: 40AK, Sterling, AK - Destination: 40AK, Sterling, AK - Airport: 40AK, Sterling Air Park, runway 06, 1,500 × 75 ft, snow ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 60; injuries: none; private; airplane ratings: single-engine sea, single-engine land; medical: class 3, with waivers/limitations; last flight review February 24, 2011; seat: front; flight hours: 1,500 total, 1,300 in this make and model ## Weather - Conditions: Visual (VMC), Day - Wind: 20° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 25 °F, dew point -6 °F - Altimeter: 30.85 inHg - Observed at: PASX, 7 nm away ## Docket (1 files) The files NTSB released with the investigation on March 29, 2011, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=78431. 359 KB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 359 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40345756&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.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.