CEN17LA228 · Thompson Angel Hawk II
Thompson Angel Hawk II · Accident: loss of engine power (total) during initial climb
From Homer Municipal Airport (5F4) to Homer Municipal Airport (5F4)
Event
- NTSB case
- CEN17LA228
- 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
- 0 · 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
Thompson Angel Hawk II
- Aircraft type
- Thompson ANGEL HAWK
- 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
- N335JT
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Homer Municipal Airport (5F4), Homer, LATo Homer Municipal Airport (5F4), Homer, LA
- Aircraft age
- About 8 years (built 2009)
- 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
- Initial climb
- 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
- Loss of engine power (total)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Aircraft › Aircraft oper/perf/capability
- Aircraft › Aircraft power plant
- Personnel issues › Task performance
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The private pilot reported that, during the accident flight, he planned to take off and circle the experimental, amateur-built airplane above the runway to check engine operation. Just after takeoff, the engine began sputtering. He made a left 180° turn to return to the runway and during the turn, the engine experienced a total loss of power. He stated that the airplane stalled when he was in the turn and he did not have enough time to recover before impacting the ground. The airplane had accumulated about 47 hours of run time and was in the initial flight test stage when the accident occurred.
The pilot reported that he had been having trouble with increased cylinder head temperatures on the converted automotive engine. The engine had experienced a total loss of power during a previous flight, but the pilot was able to land the airplane without incident. Following that event, he replaced some ignition system components and adjusted the valves. He was then able to start the engine and reported that it "ran fine" during subsequent test runs.
Postaccident examination of the airplane revealed that the fuel mixture was not adjustable in the cockpit. Examination of the engine revealed that there was melted plastic material inside the distributor rotor and the distributor drive shaft. The condition of the spark plugs was consistent with an overly lean fuel mixture and/or high temperature operation. It is likely that the melted distributor rotor was the result of the engine's high operating temperatures; the degradation of the distributor and its drive shaft would have resulted in a shift in ignition timing and a subsequent loss of engine power.
Probable cause
A total loss of engine power due to the engine’s unresolved high operating temperatures, which resulted in failure of the distributor rotor and drive shaft, and the pilot’s failure to maintain airspeed during the subsequent forced landing, which resulted in an aerodynamic stall and loss of control.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN17LA228
- Event ID
- 20170609X83633
- Case number
- CEN17LA228
- 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, coordinates. 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: 95e7659422beaa67b5abce9258ed03e7d12a7783ae8c496c57fd540053abf8ee; retrieved 2026-09-16T05:23:21.177Z.