# NTSB ERA20LA198: Piper PA-24-180, N6989P, Humboldt, TN, May 29, 2020 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: May 29, 2020, 11:30 local (16:30 UTC) - Place: Humboldt, TN - Coordinates: 35.793609, -88.878608 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=35.7936&lon=-88.8786&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Fuel contamination](https://openairdocs.org/ntsb-events/193) - Highest injury: No injuries - Injuries: 2 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Eastern Region Aviation - Parties: FAA FSDO - NTSB case key (mKey): 101345 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=ERA20LA198 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101345/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=101345 - Page: https://openairdocs.org/ntsb/ERA20LA198 ## Probable cause A partial loss of engine power due to contaminated fuel. ## 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-24-180, 2 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md?model=7102403), [All aircraft, 1,695 cases](https://openairdocs.org/ntsb-findings/01071010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Fuel contamination](https://openairdocs.org/ntsb-events/193) (defining event); cases with it: [Piper PA-24-180, 1 case](https://openairdocs.org/ntsb-events/193/sequence.md?model=7102403), [All aircraft, 225 cases](https://openairdocs.org/ntsb-events/193/sequence.md) - [Initial climb: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Piper PA-24-180, 2 cases](https://openairdocs.org/ntsb-events/440/sequence.md?model=7102403), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis New avionics had just been installed in the airplane after a 5 week wait, and the purpose of the accident flight was for the pilot to test fly the airplane with the installing mechanic. The pilot performed an uneventful preflight inspection of the airplane and after liftoff there was a reduction in engine rpm before the engine lost power completely. The pilot preformed a forced landing to a golf course, resulting in substantial damage to the fuselage and both wings. No mechanical anomalies were discovered during a postaccident examination of the engine that would have precluded normal operation; however, a fuel sample from the carburetor bowl displayed a cloudy (green/yellow) tint instead of the expected clear, blue coloring of aviation fuel. No other contamination was observed within the airplane’s fuel system and the source of the contamination could not be identified. Given this information, it is likely that the engine lost power due to contaminated fuel that migrated through the fuel system into the carburetor. ## Factual narrative On May 29, 2020, about 1130 central daylight time, a Piper PA-24-180, N6989P, was substantially damaged when it was involved in an accident near Humboldt, Tennessee. The pilot and passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, the airplane had been at Humboldt Municipal Airport (M53) Humboldt, Tennessee, for about 5 weeks to have new avionics installed in the airplane. The installation was completed on the day prior to the accident flight. The mechanic had also fueled the airplane to a total of 60 gallons that day. The purpose of the accident flight was to test and evaluate the new avionics. After the pilot performed a preflight inspection of the airplane with no anomalies found, he and the mechanic boarded the airplane for the flight. During the taxi and engine run-up, the pilot noted that “all engine parameters were indicating normal.” The pilot taxied to runway 22 and briefed the mechanic of his intentions to remain in the traffic pattern. After applying full engine power, he again noted that the engine instruments indicated “normal.” Shortly after lift-off the engine “shuttered and had a sudden reduction in RPM.” With the landing gear still down, he pitched the airplane forward, and the engine regained RPM, which brought the nose back up. After clearing over powerlines off the departure end of the runway, the engine backfired, shuttered and experienced a total loss of power. He then set up for a forced landing on a golf course. After touching down, he “applied maximum braking” before the airplane struck a wooden fence, and then a brick pillar and metal pool fence, which resulted in damage to the fuselage and both wings. Both the pilot and passenger egressed the airplane without injury. The airplane was recovered to a salvage facility and an engine examination was conducted by an airframe and powerplant (A&P) mechanic, with oversight by a Federal Aviation Administration inspector. The engine did not show evidence of impact damage and all components were present. No evidence of any preimpact mechanical malfunctions or failures of the engine were observed during the examination. A fuel sample was obtained from the carburetor bowl that appeared cloudy with a greenish-yellow tint. A second fuel sample obtained from the fuel supply hose was clear with a blue tint. A third sample obtained from the main gascolator sump was clear with blue tint. The electric fuel boost pump was powered on and functioned normally. The internal filter screen in the electric pump was clean with no debris. The mechanical fuel pump produced suction on the inlet side when the crankshaft was rotated manually via the propeller. The source of the fuel contamination was not determined. ## Aircraft - Registration: [N6989P](https://openairdocs.org/deregistered/N6989P-2021-10-30), registration cancelled 2021-10-30, S/N 24-2132, built 1960 (OpenAirDocs) - Reported make and model: Piper PA-24-180 - Registry model: [Piper PA-24-180](https://openairdocs.org/model/piper-pa-24-180) (registry code 7102403) (OpenAirDocs) - Registry engine: [Lycoming O&VO-360 series](https://openairdocs.org/engine/lycoming-o-vo-360-series) (registry code 41514, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 24-2132 - Year built: 1960 - Airframe hours: 5533.5 - Engines: Lycoming O-360A1A 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Standard, Normal - Last inspection: Annual, July 11, 2019, 75 hours before - Departed: M53, Humboldt, TN - Airport: M53, Humboldt Muni - Equipment: Electronic flight bag or handheld device, Auto-pilot, ADS-B, Stall warning system, Handheld GPS, Electronic primary flight display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 31; injuries: none; flight instructor, commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, with waivers/limitations; last flight review September 3, 2019; seat: left; restraint: lap only; flight hours: 1,593 total, 667 in this make and model, 1,474 as pilot in command, 80 in the last 90 days, 18 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 300° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: 1,800 ft overcast - Temperature: 72 °F, dew point 63 °F - Altimeter: 29.94 inHg - Observed at: MKL, 12 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 20200529007239A](https://openairdocs.org/incident/20200529007239A), May 29, 2020: Piper PA-24-180, Humboldt, TN, Substantial damage. The accident occurred on may 29, 2020 at approximately 1130CDT at the Humboldt Municipal Airport in Humboldt, TN (M53). The aircraft was a 1960 Piper single… ## Other investigations on N6989P (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 NYC65F0198](https://openairdocs.org/ntsb/NYC65F0198), May 3, 1965: Piper PA-24 (N6989P), Millbrook, NY, substantial damage ## Docket (4 files) The files NTSB released with the investigation on June 6, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=101345. 3.7 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 2.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13231639&FileExtension=pdf&FileName=6120%20for%20N6989P_Redacted-Rel.pdf - Pilot statement (item 2, PDF, 3 pages, 741 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13232137&FileExtension=pdf&FileName=Lockard%20(pilot)%20statement%20%20N6989P_Redacted-Rel.pdf - Investigative photographs (item 3, PDF, 1 page, 254 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13231531&FileExtension=pdf&FileName=Investigative%20Photographs%20-%20ERA20LA198-Rel.pdf - Engine examination (item 4, PDF, 3 pages, 373 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13264417&FileExtension=pdf&FileName=ERA20LA198%20Engine%20Examiination-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.