# NTSB WPR14LA046: Rovey Jason H RV-8, N391V, Wickenburg, AZ, November 2, 2013 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: November 2, 2013, 11:41 local (18:41 UTC) - Place: Wickenburg, AZ - Coordinates: 33.970554, -112.694999 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=33.9706&lon=-112.6950&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: No injuries - Injuries: 1 uninjured - Status: Completed, report September 8, 2015 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Admistration - NTSB case key (mKey): 88406 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR14LA046 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/88406/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=88406 - Page: https://openairdocs.org/ntsb/WPR14LA046 ## Probable cause The fatigue failure of a propeller pitch change pin due to excessive shot peening of the pin’s surface during the manufacturing process. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Propeller system: propeller hub section](https://openairdocs.org/ntsb-findings/01046114): Aircraft › Aircraft propeller/rotor · Fatigue/wear/corrosion (probable cause); cases with it: [Rovey Jason H RV-8, 1 case](https://openairdocs.org/ntsb-findings/01046114/cases.md?model=05624ZO), [All aircraft, 13 cases](https://openairdocs.org/ntsb-findings/01046114/cases.md) - [Manufacture/production](https://openairdocs.org/ntsb-findings/04013000): Organizational issues › Development · Manufacturer (probable cause); cases with it: [Rovey Jason H RV-8, 1 case](https://openairdocs.org/ntsb-findings/04013000/cases.md?model=05624ZO), [All aircraft, 17 cases](https://openairdocs.org/ntsb-findings/04013000/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: [Rovey Jason H RV-8, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=05624ZO), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Landing-landing roll: Collision with terr/obj (non-CFIT) ](https://openairdocs.org/ntsb-events/470); cases with it: [Rovey Jason H RV-8, 1 case](https://openairdocs.org/ntsb-events/470/sequence.md?model=05624ZO), [All aircraft, 10,189 cases](https://openairdocs.org/ntsb-events/470/sequence.md) - [Landing-landing roll: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Rovey Jason H RV-8, 1 case](https://openairdocs.org/ntsb-events/096/sequence.md?model=05624ZO), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis The pilot reported that, during cruise flight, he felt a sustained vibration, which he thought was from the engine or propeller, and that the airplane then started to slow down. The pilot made a forced landing to the desert, and the airplane came to rest on its nose, which caused substantial damage to the airplane. A postaccident engine run and subsequent engine examination revealed no mechanical anomalies that would have precluded normal operation. The propeller examination revealed that one of the propeller pitch change pins had broken. The pin's fracture would have resulted in the sustained vibration and loss of speed reported by the pilot. A metallurgical examination of the pin revealed that it had failed due to a fatigue crack that had progressed through about 70 percent of the pin. The fatigue crack initiated at dimples that had a depth and width consistent with excessive shot peening, which likely occurred during the manufacturing process. ## Factual narrative On November 2, 2013, at 1141 mountain standard time, an experimental Rovey Vans RV-8 airplane, N391V, made a forced landing following an engine vibration and partial loss of engine power near Wickenburg, Arizona. The owner/builder/pilot operated the airplane under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. The pilot, the sole occupant, was not injured. The airplane sustained structural damage to the left wing and firewall. Visual meteorological conditions prevailed for the local area flight, and no flight plan had been filed. The flight originated from the Wickenburg Municipal Airport (E25), Wickenburg, about 1100 the day of the accident. According to the pilot, he was a participant in a Sport Air Race League cross-country, in which participants raced against the clock. It was a 130-mile course, which departed from, and concluded at, Wickenburg Municipal Airport. The pilot stated that he was about 13 miles west of E25 at 1,200 feet agl, at maximum power and rpm, when he felt an immediate and sustained vibration, which he thought was from the engine or propeller. He radioed a mayday and stated that the airplane started to slow down. He was not able to land on United States (US) highway 60, in either direction, due to traffic. The pilot stated that he turned for Forepaugh Peak Road to make the forced landing. About 150 feet agl, he realized the airplane would not glide far enough to reach the road, and landed the airplane on the desert floor. After traveling through desert vegetation/brush, the airplane came to a stop in a nose down attitude. The pilot reported that following the forced landing, he borrowed a club propeller and bolted it to his engine. He performed a ground run of the engine with no mechanical problems encountered. The engine was disassembled at a repair station in order to perform the propeller strike inspection, followed by an engine rebuild; there were no mechanical anomalies encountered. The propeller hub was removed and examined at Ottoeson, Phoenix, Arizona, under the auspices of a Federal Aviation Administration (FAA) inspector. According to the FAA inspector, there was evidence at the hub of loading on the propeller at impact. He further reported that the propeller pins do not normally break off in accidents involving propeller strikes; however, the accident propeller pin had broken. According to engine performance downloads, it appeared that the propeller pin broke during flight. The propeller blades, hub case, and hub bearings were shipped to the National Transportation Safety Board (NTSB) metallurgical laboratory in Washington, D.C., for further examination. The hub had been disassembled prior to arrival at the metallurgical laboratory. The bearing and hub surfaces were generally in good condition with no abnormal signs of wear or pre impact damage. The propeller blades exhibited gouging and scratches along the longitudinal axis of the blade, with the blade tips damaged, primarily onthe leading edges. According to the specialist, the witness marks were consistent with ground impact damage. One of the pitch change pins had fractured from the hub face, along the bend radius where the face and pin mate. According to the specialist, the pin fracture surface had been damaged by smearing; however, the mating side fracture surface on the hub face was generally undamaged. The crack arrest and ratchet marks indicated progressive cracking, about 70 percent of the fracture surface. The specialist reported that the fatigue crack initiation site had multiple surface crack initiation sites. The surfaces of both the pin and the hub exhibited a dimpled pockmarked texture consistent with shot peening. The primary fatigue crack initiation site corresponded to a surface depression. A chemical composition was performed using the energy dispersive x-ray spectroscopy (EDS) and x-ray fluorescence (XRF), as well as hardness testing; there were discrepancies with the chemical or material composition. A detailed report is attached to the docket for this accident. ## Aircraft - Registration: [N391V](https://openairdocs.org/aircraft/N391V), registered now, S/N 82195, built 2007 (OpenAirDocs) - Reported make and model: ROVEY JASON H RV-8 - Registry model: [Rovey Jason H RV-8](https://openairdocs.org/model/rovey-jason-h-rv-8) (registry code 05624ZO) (OpenAirDocs) - Registry engine: [Superior IO-360 series](https://openairdocs.org/engine/superior-io-360-series) (registry code 59251, reciprocating) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: 82195 - Year built: 2007 - Airframe hours: 652 - Engines: Superior XP-10-360-B1A 180 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, December 7, 2012 - Departed: E25, Wickenburg, AZ - Destination: E25, Wickenburg, AZ - Airport: E25, Wickenburg Muni ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 37; injuries: none; private; airplane ratings: single-engine land; medical: class 2, with waivers/limitations; last flight review December 30, 2012; seat: front; flight hours: 1,342 total, 652 in this make and model, 1,281 as pilot in command, 21 in the last 90 days, 2 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 100° at 14 knots, gusting 17 - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 77 °F, dew point 28 °F - Altimeter: 29.95 inHg - Observed at: BXK, 33 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 20131102022919A](https://openairdocs.org/incident/20131102022919A), Nov 2, 2013: Rovey Jason H RV-8, Wickenberg, AZ, Substantial damage. During full power pratice for airracing aircraft experienced sudden sever vibration and loss of performance. Pilot throttled back to idle and then landed in… ## Docket (8 files) The files NTSB released with the investigation on August 4, 2015, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=88406. 3.9 MB in all. - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 1, .PDF, 316 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40430405&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Redacted.PDF - Engine Run Correspondence (item 2, .PDF, 116 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40430408&FileExtension=.PDF&FileName=Engine%20Run%20Correspondence-Redacted.PDF - Hartzell Propeller Information (item 3, .PDF, 90 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40430409&FileExtension=.PDF&FileName=Hartzell%20Propeller%20Information-Master.PDF - Mayday Flight Engine Data (item 4, .PDF, 67 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40430412&FileExtension=.PDF&FileName=Mayday%20Flight%20Engine%20Data-Master.PDF - Normal Flight Engine Data (item 5, .PDF, 81 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40430413&FileExtension=.PDF&FileName=Normal%20Flight%20Engine%20Data-Master.PDF - Normal vs. Mayday Engine Data (item 6, .PDF, 41 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40430414&FileExtension=.PDF&FileName=Normal%20vs.%20Mayday%20Engine%20Data-Master.PDF - J Rovey Correspondence (item 7, .PDF, 138 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40430416&FileExtension=.PDF&FileName=J%20Rovey%20Correspondence-Master.PDF - MatLab Factual (item 8, .PDF, 3.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40430418&FileExtension=.PDF&FileName=MatLab%20Factual-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.