# NTSB WPR22LA322: Ray E Roberts Kitfox V Vixen, N52367, Caldwell, ID, August 26, 2022 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Class 3 · Limited · Final report - Date: August 26, 2022, 16:20 local (22:20 UTC) - Place: Caldwell, ID - Coordinates: 43.648025, -116.63789 - Nearby events: https://openairdocs.org/map.md?lat=43.6480&lon=-116.6379&mi=10 - Phase of flight: [Initial climb](https://openairdocs.org/ntsb-phases/350) (OpenAirDocs' grouping) - Defining event: [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 105825 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR22LA322 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/105825/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=105825 - Page: https://openairdocs.org/ntsb/WPR22LA322 ## Probable cause The partial loss of engine power due to a loose wire leading to the engine’s electronic control unit (ECU). Contributing was the pilot’s exceedance of the critical angle of attack while maneuvering, which resulted in an aerodynamic stall at an altitude too low for recovery. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Electrical power system: dC power distribution system](https://openairdocs.org/ntsb-findings/01022460): Aircraft › Aircraft systems · Malfunction (probable cause); cases with it: [Ray E Roberts KITFOX V VIXEN, 1 case](https://openairdocs.org/ntsb-findings/01022460/cases.md?model=05603UJ), [All aircraft, 13 cases](https://openairdocs.org/ntsb-findings/01022460/cases.md) - [Aircraft](https://openairdocs.org/ntsb-findings/01050000): Aircraft › Aircraft power plant · Design (probable cause); cases with it: [Ray E Roberts KITFOX V VIXEN, 1 case](https://openairdocs.org/ntsb-findings/01050000/cases.md?model=05603UJ), [All aircraft, 151 cases](https://openairdocs.org/ntsb-findings/01050000/cases.md) - [Performance/control parameters: altitude](https://openairdocs.org/ntsb-findings/01062012): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible (probable cause); cases with it: [Ray E Roberts KITFOX V VIXEN, 1 case](https://openairdocs.org/ntsb-findings/01062012/cases.md?model=05603UJ), [All aircraft, 1,310 cases](https://openairdocs.org/ntsb-findings/01062012/cases.md) - [Performance/control parameters: airspeed](https://openairdocs.org/ntsb-findings/01062010): Aircraft › Aircraft oper/perf/capability · Attain/maintain not possible (probable cause); cases with it: [Ray E Roberts KITFOX V VIXEN, 1 case](https://openairdocs.org/ntsb-findings/01062010/cases.md?model=05603UJ), [All aircraft, 1,681 cases](https://openairdocs.org/ntsb-findings/01062010/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Initial climb: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Ray E Roberts KITFOX V VIXEN, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=05603UJ), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) ## Analysis The pilot planned to take off and remain in the traffic pattern as part of a post-maintenance test flight of the airplane. After climbing to about 200 ft above the runway, the engine started to gradually lose power to about 15-20% engine power. The pilot had begun maneuvering the airplane for a forced landing when it entered an aerodynamic stall. The pilot attempted to recover from the stall; however, the airplane impacted terrain and nosed over, which resulted in substantial damage to the fuselage, left wing, wing struts, and empennage. Postaccident examination determined that the power supply wire for the experimental engine’s electronic control unit (ECU) was loose in the crimped terminal. It is likely that during the flight, the intermittent power source to the ECU activated the engine’s “limp mode,” which resulted in a reduction of engine power to a level that was insufficient to maintain altitude. The engine’s limp mode is a safety feature designed to protect the engine and powertrain in automotive applications. ## Factual narrative On August 26, 2022, about 1620 mountain daylight time, an experimental, amateur-built Kitfox V Vixen, N52367, was substantially damaged when it was involved in an accident near Caldwell, Idaho. The pilot received minor injuries. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that he was conducting a post-maintenance test flight of the airplane after it had undergone a conditional inspection. The pilot reported that he had completed a flight down the runway in ground effect and then landed back on the runway. He then retook the runway for a flight around the traffic pattern. After climbing about 200 feet above the runway, the engine “slowly and continuously decreased power” to about 15 - 20% engine power. With no usable runway to land on, he turned to the left and attempted to land on a taxiway until he realized that a stall was imminent. He pushed the nose over and applied full right rudder and leveled the wings. The airplane impacted the ground and nosed over,sustaining substantial damage to the fuselage, left wing, wing struts, and the empennage as shown in figure 1. Figure 1. N52367, exhibiting substantial damage. Photo courtesy of the pilot. The airplane came to rest inverted in an open field on the airport. All major components remained attached to the airplane, except for the four propeller blades, which remained near the wreckage. Postaccident examination of the airframe revealed that the experimental Subaru EA-81 engine’s ECU would lose power when a wire bundle near the firewall was wiggled. The source of the intermittent power was traced to a loose wire crimped to a terminal. The wire was traced to the ignition switch 5-amp circuit breaker (figure 2). The mechanic who conducted the examination reported that the Subaru EA 81 engine had a “limp mode” feature which, when activated, resulted in a power reduction to about 25% to protect the engine and powertrain in automotive applications. An automotive mechanic, with multiple years of experience with Subaru engines, confirmed that an interruption of power to the ECU would activate the limp mode. Figure 2. Image of the electronic control module power supply wire and crimped terminal end. The wire was separated from the terminal postaccident. Photo courtesy of the Federal Aviation Administration. ## Aircraft - Registration: [N52367](https://openairdocs.org/aircraft/N52367), registered now, S/N V9404-0008 (OpenAirDocs) - Reported make and model: RAY E ROBERTS KITFOX V VIXEN - Registry model: [Ray E Roberts KITFOX V VIXEN](https://openairdocs.org/model/ray-e-roberts-kitfox-v-vixen) (registry code 05603UJ) (OpenAirDocs) - Registry engine: [Subaru EA-81](https://openairdocs.org/engine/subaru-ea-81) (registry code 59052, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: V9404-0008 - Year built: 2014 - Airframe hours: 323.6 - Engines: SUBARU EA-81 100 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, August 5, 2022 - Destination: Same as departure - Airport: EUL, Caldwell Executive Airport, runway 30, 5,500 × 100 ft, asphalt - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 52; injuries: minor; commercial; airplane ratings: multi-engine land, single-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; seat: left; restraint: 4-point; flight hours: 3,237 total, 1 in this make and model, 3,170 as pilot in command, 165 in the last 90 days, 62 in the last 30 days, 1.7 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 330° at 8 knots - Visibility: 10 statute miles ## 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 20220826021529A](https://openairdocs.org/incident/20220826021529A), Aug 26, 2022: Ray E Roberts KITFOX V VIXEN, Caldwell, ID, Substantial damage. PIC indicated he was taking the aircraft for a flight check after maintenance. The aircraft had not flown for several years, it had just undergone a condition… ## Docket (5 files) The files NTSB released with the investigation on April 25, 2024, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=105825. 8.6 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 11 pages, 4.7 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15794652&FileExtension=pdf&FileName=NTSB%20Form%206120.1_Redacted-Rel.pdf - Record of conversation (subaru mechanic) (item 2, PDF, 1 page, 164 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15915760&FileExtension=pdf&FileName=Record%20of%20phone%20conversation%20P_Dykstra-Rel.pdf - Airframe and engine examination report (item 3, PDF, 2 pages, 296 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15914781&FileExtension=pdf&FileName=Airframe%20and%20Engine%20Examination_Redacted-Rel.pdf - Airframe and engine exam photos (item 4, PDF, 4 pages, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15915717&FileExtension=pdf&FileName=Airframe%20and%20Engine%20Examination%20Photos-Rel.pdf - Photos (item 5, PDF, 3 pages, 2.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=15910563&FileExtension=pdf&FileName=Photos%20for%20WPR22LA322-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.