# NTSB WPR16LA047: Kevin Metzler Velocity STD RG, N133SV, Rosamond, CA, January 2, 2016 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: January 2, 2016, 14:30 local (22:30 UTC) - Place: Rosamond, CA - Coordinates: 34.884166, -118.211669 - Nearby events: https://openairdocs.org/map.md?lat=34.8842&lon=-118.2117&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 March 6, 2017 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 92533 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR16LA047 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/92533/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=92533 - Page: https://openairdocs.org/ntsb/WPR16LA047 ## Probable cause A partial loss of engine power due to failure of the No. 1 connecting rod as a result of multiple fatigue cracks for reasons that could not be determined during on postaccident examination. ## Findings NTSB's coded findings; those marked are part of the probable cause. - [Engine (reciprocating): recip engine power section](https://openairdocs.org/ntsb-findings/01058520): Aircraft › Aircraft power plant · Failure (probable cause); cases with it: [Metzler Kevin W VELOCITY STD RG, 1 case](https://openairdocs.org/ntsb-findings/01058520/cases.md?model=05633N7), [All aircraft, 233 cases](https://openairdocs.org/ntsb-findings/01058520/cases.md) - [Engine (reciprocating): recip eng cyl section](https://openairdocs.org/ntsb-findings/01058530): Aircraft › Aircraft power plant · Fatigue/wear/corrosion (probable cause); cases with it: [Metzler Kevin W VELOCITY STD RG, 1 case](https://openairdocs.org/ntsb-findings/01058530/cases.md?model=05633N7), [All aircraft, 373 cases](https://openairdocs.org/ntsb-findings/01058530/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: [Metzler Kevin W VELOCITY STD RG, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=05633N7), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Loss of engine power (partial)](https://openairdocs.org/ntsb-events/342); cases with it: [Metzler Kevin W VELOCITY STD RG, 1 case](https://openairdocs.org/ntsb-events/342/sequence.md?model=05633N7), [All aircraft, 1,858 cases](https://openairdocs.org/ntsb-events/342/sequence.md) - [Emergency descent: Off-field or emergency landing](https://openairdocs.org/ntsb-events/440); cases with it: [Metzler Kevin W VELOCITY STD RG, 1 case](https://openairdocs.org/ntsb-events/440/sequence.md?model=05633N7), [All aircraft, 3,365 cases](https://openairdocs.org/ntsb-events/440/sequence.md) ## Analysis Shortly after departure on the local flight, the private pilot observed that the engine temperature was higher than it had been on the previous day's flight. After reducing power, the engine began to surge, which prompted the pilot to return to the airport. Unable to maintain altitude, the pilot elected to land in a vacant field. The left wing sustained substantial damage during the landing. A postaccident examination of the engine revealed that the No. 1 connecting rod assembly had failed. Although the reason for the failure could not be determined, the fracture surfaces exhibited signatures of fatigue consistent with a malfunction of the connecting rod bearing, such as improper bearing size, rotation of the bearing during service, or operation of a severely worn bearing. Such conditions would result in higher-than-normal operating stress, and likely contributed to the propogation of the fatigue cracking. ## Factual narrative On January 2, 2016, about 1430 Pacific standard time, a Kevin Metzler Velocity STD RG experimental amateur-built airplane, N133SV, was substantially damaged following a loss of engine power and subsequent forced landing about 1 mile northwest of the Rosamond Skypark Airport (L00), Rosamond, California. The private pilot, who was the owner and sole occupant of the airplane, was not injured. Visual meteorological conditions prevailed for the local flight, which was being operated in accordance with 14 Code of Federal Regulations Part 91, and a flight plan was not filed. The local flight departed L00 about 5 minutes prior to the accident. In a report submitted to the National Transportation Safety Board (NTSB) investigator-in-charge (IIC), the pilot reported after taking off he climbed with the engine rpm set at about 4,500, "…which was well below the engines rated redline of 5,400 rpm." The pilot stated that when he reached an altitude of 7,000 ft, he noticed that the [engine] temperature was much higher than it had been the previous day, which prompted him to level off and reduce power. Shortly after the power reduction the engine began to surge; at this time the pilot decided to return to the departure airport, about 10 miles to the east of his location. The pilot reported that he attempted to maintain as much altitude as possible, and while en route the engine began to lose power, which made altitude more difficult to maintain. The pilot opined that when he realized that he would not be able to make it to the airport, he elected to land in a vacant field about one and one-half miles west of L00. After landing with the gear retracted, the airplane came to rest in an upright position. The airplane, which was equipped with a Subaru EG-33 engine, serial number 007708, rated at 230 horsepower, had accumulated a total of 6.8 hours since its most recent overhaul; the total engine time was unknown. The pilot reported that the most recent condition inspection was performed on December 1, 2015, at a total airframe time of 66.8 hours. An initial postaccident examination of the engine revealed that the No. 1 connecting rod assembly had failed, which resulted in the loss of power. The NTSB IIC took possession of the connecting rod assembly, in addition to two pieces that had separated from the assembly. The retained parts were shipped to the NTSB Materials Laboratory in Washington, D.C., for examination and analysis by a Senior Metallurgist. As a result of his examination, the metallurgist reported that the connecting rod assembly had fractured in four areas. An attachment bolt and nut remained attached to a fractured piece of the arm and cap portion. The second attachment bolt, a portion of the second arm, and a portion of the cap had separated from the connecting rod assembly, however, were not recovered during the investigation. Additionally, examination of the fracture faces revealed fatigue cracks emanated from multiple origins at the machined cut outarea adjacent to the through-hole for each attachment bolt. Fatigue cracks with multiple origins where also observed on the mating fracture faces. The fatigue crack origin areas were aligned and parallel to circumferential machine marks. The rough texture of the fatigue crack features was consistent with a fatigue crack that had propagated under high stress. The fatigue crack in each mating fracture propagated through at least 50% of the wall. Further, the fracture faces outside of the fatigue regions exhibited rough dimple texture features consistent with overstress separation. The round surfaces that corresponded to the location of the bearings showed evidence of rough circumferential gouge marks, but no evidence of heat tinting was observed. (Refer to the NTSB Materials Laboratory factual report, which is appended to the docket for this accident.) On January 26, 2016, under the supervision of the NTSB IIC, an examination of the engine was performed at the facilities of Outfront Motorsport, located in Santa Ana, California. With the exception of the engine's No. 1 connecting rod assembly which had failed, and the stuck piston of the pressure relief valve on the oil pump, there were no anomalies observed with the engine that would have precluded normal operation. According to the Outfront Motorsport general manager, during normal operations the pressure relief valve opens to relieve oil pressure when it is too high, and remains closed in order to build and sustain oil pressure. When observed during the postaccident examination, the piston portion of the valve was stuck closed. When the component was liquid tested to check for leakage past the piston, the valve retained liquid, which indicated that the valve was not stuck in the open position. After the piston was forced to the open position, debris was observed in the component which had kept it closed. The debris was consistent with bearing material that had invaded the area subsequent to the engine failure. ## Aircraft - Registration: [N133SV](https://openairdocs.org/aircraft/N133SV), registered now, S/N SFE 012 (OpenAirDocs) - Reported make and model: KEVIN METZLER Velocity STD RG - Registry model: [Metzler Kevin W VELOCITY STD RG](https://openairdocs.org/model/metzler-kevin-w-velocity-std-rg) (registry code 05633N7) (OpenAirDocs) - Category: Airplane, amateur-built - Serial number: SFE-012 - Year built: 2014 - Airframe hours: 66.8 - Engines: Subaru EG-33 230 horsepower reciprocating - Damage: Substantial damage - Flight: Personal, Part 91 - Airworthiness certificate: Special, Experimental (Special) - Last inspection: Condition, December 1, 2015, 7 hours before - Departed: L00, Rosamond, CA - Destination: L00, Rosamond, CA - Equipment: Electronic multifunction display, Auto-pilot, Angle of attack indicator, Electronic primary flight display ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 54; injuries: none; private; airplane ratings: single-engine land; medical: class 3, with waivers/limitations; last flight review August 25, 2014; seat: left; restraint: 3-point; flight hours: 847 total, 67 in this make and model, 807 as pilot in command, 11 in the last 90 days, 9 in the last 30 days, 1 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 60° at 8 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 52 °F, dew point 12 °F - Altimeter: 30.11 inHg - Observed at: WJF, 8 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 20160102006459A](https://openairdocs.org/incident/20160102006459A), Jan 2, 2016: Metzler Kevin W VELOCITY STD RG, Rosamond, CA, Substantial damage. Subaru automotive engine failure caused loss of power. Emergency gear up landing resulted in substantial damage to aircraft's monocoque design structure and a… ## Docket (4 files) The files NTSB released with the investigation on January 19, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=92533. 2.0 MB in all. - Materials Laboratory Factual Report 16-018 (item 1, .PDF, 189 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40448439&FileExtension=.PDF&FileName=Materials%20Laboratory%20Factual%20Report%2016-018-Master.PDF - Pilot/Operator Aircraft Accident Report, NTSB Form 6120.1 (item 2, .PDF, 671 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40448444&FileExtension=.PDF&FileName=Pilot%2FOperator%20Aircraft%20Accident%20Report,%20NTSB%20Form%206120.1-Master.PDF - Engine Examination (item 3, .PDF, 175 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40448453&FileExtension=.PDF&FileName=Engine%20Examination%20-Master.PDF - Release of Aircraft Wreckage, NTSB Form 6120.15 (item 4, .PDF, 966 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40448454&FileExtension=.PDF&FileName=Release%20of%20Aircraft%20Wreckage,%20NTSB%20Form%206120.15-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.