# NTSB WPR23LA314: Reynolds Ronald B Team Acft Z-MAX, N440ZM, Rigby, ID, August 9, 2023 - Type: NTSB accident investigation - Classification: Accident · Serious injuries · Class 3 · Limited · Final report - Date: August 8, 2023, 18:24 local (Aug 9, 2023, 00:24 UTC) - Place: Rigby, ID - Coordinates: 43.640725, -111.92987 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=43.6407&lon=-111.9299&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) - Highest injury: Serious injuries - Injuries: 1 serious - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: FAA - NTSB case key (mKey): 192869 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR23LA314 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/192869/pdf - Page: https://openairdocs.org/ntsb/WPR23LA314 ## Probable cause The loss of engine power during takeoff due to inadequately secured wires, which resulted in the wearing of the wires’ sheaths and the grounding of the airplane’s electrical system. Contributing to the accident was the pilot’s failure to maintain airplane control during the flight. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip eng wiring](https://openairdocs.org/ntsb-findings/01058597): Aircraft › Aircraft power plant · Fatigue/wear/corrosion (probable cause); cases with it: [Reynolds Ronald B TEAM ACFT Z-MAX, 1 case](https://openairdocs.org/ntsb-findings/01058597/cases.md?model=05620AF), [All aircraft, 8 cases](https://openairdocs.org/ntsb-findings/01058597/cases.md) - [Engine (reciprocating): recip eng wiring](https://openairdocs.org/ntsb-findings/01058597): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Reynolds Ronald B TEAM ACFT Z-MAX, 1 case](https://openairdocs.org/ntsb-findings/01058597/cases.md?model=05620AF), [All aircraft, 8 cases](https://openairdocs.org/ntsb-findings/01058597/cases.md) - [Engine (reciprocating): recip eng wiring](https://openairdocs.org/ntsb-findings/01058597): Aircraft › Aircraft power plant · Incorrect service/maintenance (probable cause); cases with it: [Reynolds Ronald B TEAM ACFT Z-MAX, 1 case](https://openairdocs.org/ntsb-findings/01058597/cases.md?model=05620AF), [All aircraft, 8 cases](https://openairdocs.org/ntsb-findings/01058597/cases.md) - [Use of equip/info: aircraft control](https://openairdocs.org/ntsb-findings/02063040): Personnel issues › Task performance · Pilot (probable cause); cases with it: [Reynolds Ronald B TEAM ACFT Z-MAX, 1 case](https://openairdocs.org/ntsb-findings/02063040/cases.md?model=05620AF), [All aircraft, 9,295 cases](https://openairdocs.org/ntsb-findings/02063040/cases.md) - [Performance/control parameters](https://openairdocs.org/ntsb-findings/01062000): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Reynolds Ronald B TEAM ACFT Z-MAX, 1 case](https://openairdocs.org/ntsb-findings/01062000/cases.md?model=05620AF), [All aircraft, 1,269 cases](https://openairdocs.org/ntsb-findings/01062000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Takeoff: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342) (defining event); cases with it: [Reynolds Ronald B TEAM ACFT Z-MAX, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=05620AF), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Takeoff: Loss of control in flight](https://openairdocs.org/ntsb-events/240); cases with it: [Reynolds Ronald B TEAM ACFT Z-MAX, 1 case](https://openairdocs.org/ntsb-events/240/sequence.md?model=05620AF), [All aircraft, 5,002 cases](https://openairdocs.org/ntsb-events/240/sequence.md) ## Analysis Before takeoff for a local flight, the pilot emptied the wing tanks, cleaned the carburetors and fuel pump, and test ran the engine. The airplane had not flown in 8 years. A witness saw the airplane taxi up and down the taxiway multiple times both the day before and day of the accident, and then saw it depart on the accident flight. The witness heard the engine sputtering shortly after takeoff and stated that it was not operating at full power. The witness recalled the airplane made an abrupt left turn above the airport, and while in the turn, the left wing dropped sharply. The airplane then descended and impacted the ground with the left wing. Postaccident examination of the wreckage revealed that two wires from the starter solenoid to the voltage regulator were inadequately secured and worn on their outer sheath, revealing the internal copper wires. The wires were routed across the right forward side of the engine support structure. The copper wires were in contact with the support structure, which likely grounded the airplane’s electrical system and caused the engine to lose power. The sudden drop of the left wing during the turn was consistent with the pilot exceeding the airplane’s critical angle of attack during the turn, resulting in an aerodynamic stall at an altitude too low for recovery. ## Factual narrative On August 8, 2023, about 1824 mountain daylight time, an experimental amateur-built Team Acft Z-Max airplane, N440ZM, was substantially damaged when it was involved in an accident near Rigby, Idaho. The private pilot was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot, who was also the airplane owner, reported that he had not flown the airplane in 8 years. The day before the accident flight, he drained and refilled the fuel tanks, cleaned the carburetors and fuel pump, and test ran the engine. He completed four taxi tests at Rigby Airport (U56) the day before and the day of the accident, before departing on the accident flight. The pilot does not remember the accident flight. A witness reported the pilot told him that he had been working on the engine because he was having problems getting it to start. On the day before and the day of the accident flight, the pilot was working on the engine and was seen taxiing the airplane up and down the taxiway. Shortly after, the witness saw the airplane depart on the accident flight. The witness stated the airplane flew past his hangar about 100-200 ft above ground level (agl) heading southbound. As the airplane passed his hangar, he heard the engine sputtering and it was not operating at full power. He remembers the airplane making an abrupt left turn above the airport, and while in the turn, the left wing dropped sharply. The airplane then descended and impacted the ground with the left wing. Examination of the accident site revealed that the airplane impacted the taxiway and came to rest in the runway safety area, on the east side of the airport. The header fuel tank separated from the airplane during the accident sequence and was burned. The fuselage and wings sustained substantial damage and did not catch fire. Postaccident examination of the wreckage revealed that two red wires from the starter solenoid to the voltage regulator were inadequately secured and worn on their outer sheath, revealing the internal copper wires. The wires were routed across the right forward side of the engine support structure. The copper wires were in contact with the metal support structure. Figure 1- Wire routing. Figure 2- Wire sheath worn. The airplane’s maintenance records were not available during the investigation. FAA Advisory Circular 43.13-1B Section 8, paragraph 11-96, “Wiring Installation Inspection Requirements,” states that wires and cables should be inspected for adequacy of support, protection, and general condition throughout. Ensure that wires and cables are routed in such a manner that chafing will not occur against the airframe or other components. ## Aircraft - Registration: [N440ZM](https://openairdocs.org/deregistered/N440ZM-2023-12-19), registration cancelled 2023-12-19, S/N 440, built 1992 (OpenAirDocs) - Reported make and model: REYNOLDS RONALD B TEAM ACFT Z-MAX - Registry model: [Reynolds Ronald B TEAM ACFT Z-MAX](https://openairdocs.org/model/reynolds-ronald-b-team-acft-z-max) (registry code 05620AF) (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: 440 - Year built: 1992 - Airframe hours: 268 - Engines: Zenoah G50C 50 horsepower reciprocating - Damage: Substantial damage - Fire: On-Ground - Flight: Personal, Part 91 - Operator: Reynolds Ronald B - Registered owner: Reynolds Ronald B - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Annual, August 7, 2023, 1 hours before - Airport: U56, Rigby Airport, runway 19, 3,727 × 50 ft, asphalt ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 66; injuries: serious; private; airplane ratings: single-engine land; medical: basicmed; last flight review August 20, 2021; seat: single; restraint: 4-point; flight hours: 362 total, 269 in this make and model, 309 as pilot in command ## Weather - Conditions: Visual (VMC), Day - Wind: 180° at 6 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 73 °F, dew point 46 °F - Altimeter: 30.10 inHg - Observed at: KIDA, 9 nm away - METAR: KIDA 082353Z 18006KT 10SM CLR 23/08 A3010 RMK AO2 SLP155 T02330078 10239 20178 58007 ## 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 20230808012759A](https://openairdocs.org/incident/20230808012759A), Aug 8, 2023: Reynolds Ronald B TEAM ACFT Z-MAX, Rigby, ID, Substantial damage. After completing [privacy data omitted] aircraft annual condition and maintenance inspection, the pilot took off from U56 RUNWAY19 at approximately 1825 local… 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.