# NTSB WPR15LA106: Grumman Acft ENG Cor-Schweizer G 164A, N4863, Alfalfa, OR, February 18, 2015 - Type: NTSB accident investigation - Classification: Accident · No injuries · Limited investigation · Final report - Date: February 17, 2015, 18:19 local (Feb 18, 2015, 02:19 UTC) - Place: Alfalfa, OR - Coordinates: 44.095001, -120.943336 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=44.0950&lon=-120.9433&mi=10 - Phase of flight: [Emergency descent](https://openairdocs.org/ntsb-phases/600) (OpenAirDocs' grouping) - Defining event: [Emergency descent: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed, report May 1, 2017 - Report: Approved by Office Director - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 90748 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR15LA106 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/90748/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=90748 - Page: https://openairdocs.org/ntsb/WPR15LA106 ## Probable cause A total loss of engine power after takeoff for reasons that could not be determined, because examination of the engine did not reveal any mechanical anomalies that would have precluded normal operation. ## 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: [Grumman Acft ENG Cor-Schweizer G-164A, 8 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=3952801), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Emergency descent: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 10 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=3952801), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Landing: Landing area overshoot](https://openairdocs.org/ntsb-events/380); cases with it: [Grumman Acft ENG Cor-Schweizer G-164A, 2 cases](https://openairdocs.org/ntsb-events/380/sequence.md?model=3952801), [All aircraft, 400 cases](https://openairdocs.org/ntsb-events/380/sequence.md) ## Analysis The commercial pilot/owner, an airframe and powerplant mechanic with inspection authorization privileges, performed an annual inspection on the airplane in order to return it to service after it had been in storage for about 2 years. Ground engine run-up checks revealed no discrepancies, and he decided to perform a test flight. After takeoff, the engine sputtered and lost power, and the pilot returned to the airport for a precautionary landing. The airplane overran the runway, struck a tire, and came to rest inverted. A postaccident engine run revealed no mechanical discrepancies that would have precluded normal operation. The reason for the loss of engine power was not determined. ## Factual narrative On February 17, 2015, at 1819 Pacific standard time, a Grumman Aircraft Eng. Corp-Schweizer G-164A airplane, N4863, experienced a loss of engine power during takeoff on a local area flight from the Goering Ranches Airport (50OR), Alfalfa, Oregon. The commercial pilot/owner operated the airplane under the provision of 14 Code of Federal Regulations Part 91 as a maintenance test flight. The pilot was not injured, and the airplane sustained substantial damage. Visual meteorological conditions prevailed for the flight that departed 50OR about 1815.According to the pilot, the airplane had been in storage for the past 2 years. He stated that he was also an airframe and power plant mechanic with inspection authorization privileges, and he had recently finished an annual inspection of the airplane. His intent was to perform a maintenance return to service flight. The pilot stated that the airplane had 25 gallons of fuel on board. He performed two 45-minute run-ups with no discrepancies encountered. The pilot stated that he then readied the airplane for the maintenance flight. After takeoff, the engine sputtered and lost power. The pilot returned to land at 50OR, but overran the runway. The airplane struck a tire, and came to rest inverted, which caused structural damage to the tail section. The pilot/owner did not return the National Transportation Safety Board Form 6120.1 titled Pilot Operator Accident/Incident Form. A Federal Aviation Administration (FAA) inspector, inspected the airplane, and performed an engine run-up. The visual inspection revealed that the propeller blades were bent, but there was enough clearance to perform an engine run. Fuel samples were obtained from both wings and the sump; the fuel samples were free of debris, and no water was present. The engine started with no issues, and the engine was run at 700 rpm. They were able to perform a magneto check during the engine run with no discrepancies encountered. They were not able to perform the run up at a higher rpm, due to engine vibration. ## Aircraft - Registration: [N4863](https://openairdocs.org/aircraft/N4863), registered now, S/N 1016, built 1972 (OpenAirDocs) - Reported make and model: GRUMMAN ACFT ENG COR-SCHWEIZER G 164A - Registry model: [Grumman Acft ENG Cor-Schweizer G-164A](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164a) (registry code 3952801) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 1016 - Year built: 1972 - Airframe hours: 6217 - Engines: Prat and Whitney Aircraft R-1340-AN-1 600 horsepower reciprocating - Damage: Substantial damage - Flight: Flight test, Part 91 - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, August 2, 2012 - Departed: 50OR, Alfalfa, OR - Destination: 50OR, Alfalfa, OR - Airport: 50OR, Goering Ranches, runway 35, 5,500 × 60 ft, dirt - Equipment: Unknown ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 62; injuries: none; commercial; airplane ratings: single-engine sea, single-engine land, multi-engine land; instrument ratings: airplane; medical: class 2, with waivers/limitations; seat: left; flight hours: 10,000 total, 3,000 in this make and model, 50 in the last 90 days ## Weather - Conditions: Visual (VMC), Dusk - Wind: 330° at 4 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 41 °F, dew point 32 °F - Altimeter: 30.20 inHg - Observed at: BDN, 11 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 20150217001189A](https://openairdocs.org/incident/20150217001189A), Feb 17, 2015: Grumman Acft Eng Cor-Schweizer G-164A, Alfalfa, OR, Substantial damage. The aircraft engine lost power over airport and the pilot landed the aircraft in an adjacent field. On rollout the left landing gear wheel struck a set of old… ## Docket (2 files) The files NTSB released with the investigation on March 31, 2017, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=90748. 108 KB in all. - FAA Correspondence (item 1, .PDF, 78 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450588&FileExtension=.PDF&FileName=FAA%20Correspondence-Master.PDF - Record of Conversation - FAA Inspector Leonetti (item 2, .PDF, 30 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=40450589&FileExtension=.PDF&FileName=Record%20of%20Conversation%20-%20FAA%20Inspector%20Leonetti-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.