WPR17LA067 · Guarino Vans RV-8
Guarino Vans RV-8 · Accident: loss of engine power (partial) en route
From Half Moon Bay Airport (HAF) to Auburn Municipal Airport (AUN)
Event
- NTSB case
- WPR17LA067
- 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
Guarino Vans RV-8
- Aircraft type
- Guarino VANS
- 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
- N470LM
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Half Moon Bay Airport (HAF), Half Moon Bay, CATo Auburn Municipal Airport (AUN), Auburn, CA
- Aircraft age
- About 9 years (built 2008)
- 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
- En route · cruise
- 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 (partial)
- 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
- Not determined › Not determined
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot stated that while en route on the personal cross-country flight, the engine experienced a loss of thrust, and the airspeed slowed. The propeller was windmilling, but the throttle had no effect on the engine. The pilot noted that the propeller circuit breaker had popped out but did not note any other indications of an anomaly in the cockpit. In addition, with the engine operating at partial power, the pilot was unable to maintain level flight so he configured the airplane for the best glide speed. He attempted to regain engine power twice and switched fuel tanks, to no avail. The pilot made a forced landing in a soft field, which resulted in substantial damage to the airframe.
A postaccident examination noted no evidence of engine mechanical anomalies or thermal distress. There were several wires and a wiring harness disconnected in between the cockpit and the firewall; it is unknown if this happened after impact. During an attempted engine test, a fuel source was rigged to the left fuel tank; the starter solenoid was heard activating, but the engine would not start. An external power source was used in an attempt to start the engine; the engine cranked but would not start. Fuel continuity and pressure in the system was confirmed. The fragmentation of the wreckage, specifically the electrical system, precluded a definitive determination of the cause of the engine failure.
Probable cause
A partial loss of engine power for reasons that could not be determined due to the fragmentation of the electrical system.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR17LA067
- Event ID
- 20170228X14159
- Case number
- WPR17LA067
- 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: local date, investigation status. Values present in the bulk record are kept.
- The date is the local date; the NTSB stores the UTC date 2017-02-24.
- API snapshot SHA-256: ea5fd3f7c81f9a31e4723e11f1b7a433f2fe96a4f576383fe9ebe8eb98b48398; retrieved 2026-09-16T05:02:47.515Z.