WPR15LA001 · Gaston Thomas D THUNDER MUSTANG
Gaston Thomas D THUNDER MUSTANG · Accident on approach
From Council Municipal Airport (U82) to Council Municipal Airport (U82)
Event
- NTSB case
- WPR15LA001
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 1 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Gaston Thomas D THUNDER MUSTANG
- Aircraft type
- Gaston Thomas THUNDER MUSTANG
- Category
- Airplane
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N51TG
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Council Municipal Airport (U82), Council, IDTo Council Municipal Airport (U82), Council, ID
- Aircraft age
- About 9 years (built 2005)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Approach · VFR pattern final
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Unknown or undetermined
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Destroyed
Cause areas
- Aircraft › Fluids/miscellaneous hardware
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot/builder had not flown his experimental amateur-built airplane for several months while he performed a top overhaul of the engine. During the first flight after completion of the overhaul, a witness observed the pilot start the airplane, complete an engine run-up, and take off uneventfully. Shortly thereafter, the pilot radioed that he was having an engine oil pressure issue and was returning to the airport. The witness then observed the airplane on the downwind leg of the traffic pattern. The airplane turned onto the base leg about "1/2 mile closer than normal," and, upon turning onto the final leg of the traffic pattern, began a series of descending S-turns. The airplane then made a "hard" right turn away from the runway and impacted rocky terrain. The airplane was destroyed, and the pilot was fatally injured.
Postaccident examination of the engine revealed foreign material in the oil consistent with the remnants of blue paper shop towels. This contamination was likely the cause of a low oil pressure indication. Recorded data indicated that the engine experienced a loss of oil pressure about two minutes before the accident. All other recorded parameters revealed no anomalies, with the engine indicating about 2,000 rpm at the time of impact, which may suggest that the pilot was trying to limit internal damage to the engine by reducing its power setting. Given the witness account of the airplane turning onto the base leg closer than normal, it is possible that the observed s-turns on the final leg of the approach, as well as the turn away from the runway, were an attempt to lose altitude and speed so that the airplane could be landed on the runway. It is likely that the pilot's preoccupation with the low oil pressure indication contributed to a loss of control while maneuvering for landing. Toxicological testing of the pilot was positive for diphenhydramine; however, there was no evidence to suggest that this may have contributed to the accident.
Probable cause
The pilot's failure to maintain control while maneuvering for landing following a loss of oil pressure. Contributing to the accident was foreign material contamination of the oil system due to improper maintenance.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR15LA001
- Event ID
- 20141003X71438
- Case number
- WPR15LA001
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: e53d97a52e73eb4da18e53a5f1640c54996b06ac78f7e0fd7971bad7fda3b2a1; retrieved 2026-09-14T17:27:05.982Z.