# NTSB GAA16CA102: Piper PA 18A, N2791P, Girdwood, AK, December 21, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Data collection · Final report - Date: December 21, 2015, 14:00 local (23:00 UTC) - Place: Girdwood, AK - Coordinates: 60.939998, -149.149993 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=60.9400&lon=-149.1500&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering: Fuel contamination](https://openairdocs.org/ntsb-events/193) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed, report April 5, 2016 - Report: Approved by Office Director - NTSB office: General Aviation Accidents - Parties: Federal Aviation Administration - NTSB case key (mKey): 92596 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=GAA16CA102 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/92596/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=92596 - Page: https://openairdocs.org/ntsb/GAA16CA102 ## Probable cause Fuel contamination resulting in the loss of engine power, a forced landing on a highway, and subsequent right wing impact with highway signage. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Fluids: fuel](https://openairdocs.org/ntsb-findings/01071010): Aircraft › Fluids/misc hardware · Fluid condition (probable cause); cases with it: [Piper PA-18A, 2 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md?model=7101804), [All aircraft, 1,695 cases](https://openairdocs.org/ntsb-findings/01071010/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-18A, 13 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=7101804), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Knowledge: knowledge of equipment](https://openairdocs.org/ntsb-findings/02032015): Personnel issues › Experience/knowledge · Pilot; cases with it: [Piper PA-18A, 1 case](https://openairdocs.org/ntsb-findings/02032015/cases.md?model=7101804), [All aircraft, 69 cases](https://openairdocs.org/ntsb-findings/02032015/cases.md) - [Temp/humidity/pressure: low temperature](https://openairdocs.org/ntsb-findings/03031010): Environmental issues › Conditions/weather/phenomena · Effect on equipment; cases with it: [Piper PA-18A, 1 case](https://openairdocs.org/ntsb-findings/03031010/cases.md?model=7101804), [All aircraft, 8 cases](https://openairdocs.org/ntsb-findings/03031010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering: Fuel contamination](https://openairdocs.org/ntsb-events/193) (defining event); cases with it: [Piper PA-18A, 1 case](https://openairdocs.org/ntsb-events/193/sequence.md?model=7101804), [All aircraft, 225 cases](https://openairdocs.org/ntsb-events/193/sequence.md) - [Maneuvering: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341); cases with it: [Piper PA-18A, 3 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=7101804), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Landing: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Piper PA-18A, 10 cases](https://openairdocs.org/ntsb-events/470/sequence.md?model=7101804), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) ## Analysis According to the pilot, the airplane departed the runway and climbed to 3000 feet above ground level. She reported that while maneuvering, the airplane lost engine power. After several attempts to restart the engine, the pilot made a forced landing on a highway bridge. She reported that during the landing roll, the airplane's right wing struck a sign that was affixed to the bridge. According to the pilot, at the time of the accident, there were twenty gallons of fuel on board the airplane. She reported that the airframe and power plant mechanic removed approximately two cups of water from the fuel tanks after the accident in preparation for the airplane's recovery. The airplane sustained substantial damage to the right wing spar and aileron. ## Factual narrative According to the pilot, the airplane departed the runway and climbed to 3000 feet above ground level. She reported that while maneuvering, the airplane lost engine power. After several attempts to restart the engine, the pilot made a forced landing on a highway bridge. She reported that during the landing roll, the airplane's right wing struck a sign that was affixed to the bridge. According to the pilot, at the time of the accident, there were twenty gallons of fuel on board the airplane. She reported that the airframe and power plant mechanic removed approximately two cups of water from the fuel tanks after the accident in preparation for the airplane's recovery. The airplane sustained substantial damage to the right wing spar and aileron. ## Aircraft - Registration: [N2791P](https://openairdocs.org/aircraft/N2791P), registered now, S/N 18-4426, built 1955 (OpenAirDocs) - Reported make and model: PIPER PA 18A (105SPECIAL) - Registry model: [Piper PA-18A](https://openairdocs.org/model/piper-pa-18a) (registry code 7101804) (OpenAirDocs) - Registry engine: [Lycoming 0-320 series](https://openairdocs.org/engine/lycoming-0-320-series) (registry code 41508, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 18-4426 - Year built: 1955 - Airframe hours: 3396.6 - Engines: LYCOMING O-320-A2B 160 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Operator: Okonek Kellie L - Registered owner: Okonek Kellie L - Airworthiness certificate: Standard, Normal - Last inspection: Annual, January 6, 2015 - Departed: AQY, GIRDWOOD, AK - Destination: AQY, GIRDWOOD, AK - Airport: AQY, Girdwood ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 35; injuries: none; private; airplane ratings: single-engine land; medical: class 3, without waivers/limitations; last flight review June 27, 2015; seat: front; restraint: 3-point; flight hours: 263.3 total, 206.3 in this make and model, 263.3 as pilot in command, 0.5 in the last 90 days, 0.5 in the last 30 days, 0.5 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 14 °F, dew point 10 °F - Altimeter: 29.17 inHg - Observed at: ANC, 3 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 20151221020179A](https://openairdocs.org/incident/20151221020179A), Dec 21, 2015: Piper PA-18A, Girdwood, AK, Substantial damage. Aircraft departed Girdwood Airport (aqv) to the south. Pilot stated they were at 3000 ft AGL approx 10 miles from Girdwood when the engine quit producing… ## Other investigations on N2791P (5) 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 ANC20CA041](https://openairdocs.org/ntsb/ANC20CA041), Apr 7, 2020: Piper PA 18A (N2791P), Chickaloon, AK, substantial damage. Probable cause: The pilot's selection of unsuitable terrain for landing, which necessitated a go-around, and her subsequent failure to maintain clearance from rising mountainous terrain. - [NTSB GAA17CA027](https://openairdocs.org/ntsb/GAA17CA027), Oct 14, 2016: Piper PA18 (N2791P), Palmer, AK, substantial damage. Probable cause: The airplane's encounter with a depression while the pilot applied excessive braking during the landing roll on a grass airstrip, which resulted in a nose-over. - [NTSB ANC71DAG54](https://openairdocs.org/ntsb/ANC71DAG54), Nov 26, 1970: Piper PA-18A (N2791P), Pt.Alsworth, AK, substantial damage - [NTSB ANC69D0041](https://openairdocs.org/ntsb/ANC69D0041), Aug 11, 1968: Piper PA-18A (N2791P), Chitina, AK, substantial damage - [NTSB ANC66D0048](https://openairdocs.org/ntsb/ANC66D0048), Aug 15, 1965: Piper PA-18A (N2791P), Soldotna, AK, substantial damage ## Docket (2 files) The files NTSB released with the investigation on March 11, 2016, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=92596. 1.0 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 802 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40437664&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Photos (item 2, .PDF, 248 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40437665&FileExtension=.PDF&FileName=Photos-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.