# NTSB WPR17LA067: Guarino Vans, N470LM, Marysville, CA, February 24, 2017 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Limited investigation · Final report - Date: February 23, 2017, 17:30 local (Feb 24, 2017, 01:30 UTC) - Place: Marysville, CA - Coordinates: 39.36972, -121.423614 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.3697&lon=-121.4236&mi=10 - Phase of flight: [Enroute](https://openairdocs.org/ntsb-phases/400) (OpenAirDocs' grouping) - Defining event: [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Minor injuries - Injuries: 2 minor - Status: Completed, report May 28, 2020 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 94781 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR17LA067 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/94781/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=94781 - Page: https://openairdocs.org/ntsb/WPR17LA067 ## Probable cause A partial loss of engine power for reasons that could not be determined due to the fragmentation of the electrical system. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Not determined](https://openairdocs.org/ntsb-findings/05000000): Not determined › Not determined · Unknown/Not determined (probable cause); cases with it: [Guarino Michael John VANS RV-8, 1 case](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=056259S), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) - [Power plant: powerplant wiring](https://openairdocs.org/ntsb-findings/01057197): Aircraft › Aircraft power plant · Not specified; cases with it: [Guarino Michael John VANS RV-8, 1 case](https://openairdocs.org/ntsb-findings/01057197/cases.md?model=056259S), [All aircraft, 1 case](https://openairdocs.org/ntsb-findings/01057197/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Enroute-cruise: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Guarino Michael John VANS RV-8, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=056259S), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Enroute-cruise: Attempted remediation/recovery](https://openairdocs.org/ntsb-events/060); cases with it: [Guarino Michael John VANS RV-8, 1 case](https://openairdocs.org/ntsb-events/060/sequence.md?model=056259S), [All aircraft, 1,422 cases](https://openairdocs.org/ntsb-events/060/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Guarino Michael John VANS RV-8, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=056259S), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis 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. ## Factual narrative On February 23, 2017, about 1730 Pacific standard time, an amateur-built Guarino, Vans RV-8 airplane, N470LM, was substantially damaged during a forced landing in a field in Marysville, California. The airline transport pilot and passenger sustained minor injuries. The airplane was registered to and operated by the pilot as a Title 14 Code of Federal Regulations Part 91 personal flight. Visual meteorological conditions prevailed, and no flight plan had been filed for the cross country flight. The flight originated from Half Moon Bay Airport, Half Moon Bay, California, about 1600 with a planned destination of Auburn, California. The pilot stated that he departed with full fuel in the wing tanks earlier that day from an airport in Davis, California. He landed in Half Moon Bay for lunch and departed about 1600 with a planned destination of Auburn. As he approached the vicinity of Auburn, he decided to divert over to the Oroville Dam area to sightsee. He maneuvered around the area at about 2,000 ft above ground level (agl) and then started the leg back to Auburn. While en route, the engine experienced a loss of thrust and the pilot could feel the airspeed slow. The propeller was still windmilling, but the throttle had no effect on the engine. He noted that the propeller circuit breaker had popped out, but there were no other indications of an anomaly in the cockpit. The pilot further stated that with the engine operating at partial power, he was unable to maintain level flight and configured for the best glide speed. He attempted to restart the engine twice and switched fuel tanks, to no avail. The pilot made a forced landing in a soft field, resulting in the airframe sustaining substantial damage. The pilot estimated that at the time of the accident he had enough fuel on board for about 1.5 hours of flight time. A post accident examination and attempted engine operational test was completed. There was no apparent visible evidence of engine mechanical anomalies or thermal distress. Fuel continuity and pressure in the system was confirmed. There were several wires and a wiring harness disconnected in between the cockpit and the firewall; it is unknown if this happened after impact. A fuel source was rigged to the left fuel tank and investigators attempted to start the engine. The starter solenoid was heard to activate, but the engine would not start. An external source of power was used in attempt to start the engine and the engine cranked but would not start. A starting fluid was sprayed into the air intake, and investigators again attempted to run the engine; the engine temporarily started, but then quit after 1-3 seconds. The fragmentation of the electrical system precluded investigators from definitively determining the engine failure. ## Aircraft - Registration: [N470LM](https://openairdocs.org/aircraft/N470LM), registered now, S/N 80070 (OpenAirDocs) - Reported make and model: GUARINO Vans (RV-8) - Registry model: [Guarino Michael John VANS RV-8](https://openairdocs.org/model/guarino-michael-john-vans-rv-8) (registry code 056259S) (OpenAirDocs) - Registry engine: [Amateur-built UNKNOWN ENG](https://openairdocs.org/engine/amateur-built-unknown-eng) (registry code 99999) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 80070 - Year built: 2008 - Airframe hours: 250 - Engines: Subaru H6 190 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Departed: HAF, HALF MOON BAY, CA - Destination: AUN, Auburn, CA - Airport: AUN, Auburn Muni - Equipment: Handheld GPS ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 27; injuries: minor; commercial, military, airline transport; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 1, without waivers/limitations; seat: front; restraint: 5-point; flight hours: 1,379 total, 3,835 in this make and model, 500 as pilot in command, 150 in the last 90 days, 60 in the last 30 days ## Weather - Conditions: Visual (VMC), Day - Wind: variable at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 50 °F, dew point 28 °F - Altimeter: 30.14 inHg - Observed at: KBAB, 14 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 20170223006169A](https://openairdocs.org/incident/20170223006169A), Feb 23, 2017: Guarino Michael John VANS RV-8, Bangor, CA, Substantial damage. Bangor, CA: N470LM, vans RV-8, stated they had lost engine power and were going to divert to bab. Pilot stated they were unable to make it to bab and they… ## Docket (4 files) The files NTSB released with the investigation on January 21, 2020, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=94781. 4.1 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 3.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40480116&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Witness Statement (item 2, .PDF, 11 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40480117&FileExtension=.PDF&FileName=Witness%20Statement-Master.PDF - Engine Examination Notes (item 3, .PDF, 73 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40480118&FileExtension=.PDF&FileName=Engine%20Examination%20Notes-Master.PDF - Pictures (item 4, .PDF, 201 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40480119&FileExtension=.PDF&FileName=Pictures-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.