# NTSB WPR18LA189: Grumman G164B, N6696K, Colusa, CA, July 9, 2018 - Type: NTSB accident investigation - Classification: Accident · No injuries · Class 3 · Limited · Final report - Date: July 9, 2018, 11:00 local (18:00 UTC) - Place: Colusa, CA - Coordinates: 39.214443, -122.009445 (estimated) - Nearby events: https://openairdocs.org/map.md?lat=39.2144&lon=-122.0094&mi=10 - Phase of flight: [Maneuvering](https://openairdocs.org/ntsb-phases/450) (OpenAirDocs' grouping) - Defining event: [Maneuvering-low-alt flying: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) - Highest injury: No injuries - Injuries: 1 uninjured - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 97719 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR18LA189 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/97719/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=97719 - Page: https://openairdocs.org/ntsb/WPR18LA189 ## Probable cause Total loss of engine power for reasons that could not be determined based on the available information. ## 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; cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 11 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=3952802), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) - [Engine (reciprocating)](https://openairdocs.org/ntsb-findings/01058500): Aircraft › Aircraft power plant · Unknown/Not determined (probable cause); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 2 cases](https://openairdocs.org/ntsb-findings/01058500/cases.md?model=3952802), [All aircraft, 497 cases](https://openairdocs.org/ntsb-findings/01058500/cases.md) ## Sequence of events The events NTSB coded, in order, by phase of flight. The defining event best describes what happened. - [Maneuvering-low-alt flying: Loss of engine power (total)](https://openairdocs.org/ntsb-events/341) (defining event); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 13 cases](https://openairdocs.org/ntsb-events/341/sequence.md?model=3952802), [All aircraft, 3,820 cases](https://openairdocs.org/ntsb-events/341/sequence.md) - [Landing: Nose over/nose down](https://openairdocs.org/ntsb-events/096); cases with it: [Grumman Acft ENG Cor-Schweizer G-164B, 19 cases](https://openairdocs.org/ntsb-events/096/sequence.md?model=3952802), [All aircraft, 2,287 cases](https://openairdocs.org/ntsb-events/096/sequence.md) ## Analysis The pilot was performing an aerial application flight when the engine made a popping noise and began to vibrate. The airplane slowed and the pilot initiated a turn toward a nearby runway. The engine subsequently lost total power and the airplane impacted terrain, where it nosed over and came to rest inverted, resulting in substantial damage. The operator reported that the engine was sent to a repair and overhaul facility following the accident and that no anomalies were found that would have precluded normal operation. ## Factual narrative On July 9, 2018, about 1100 Pacific daylight time, a Grumman G-164B airplane, N6696K, was substantially damaged when it was involved in an accident near Colusa, California. The commercial pilot was not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 137 aerial application flight. The pilot reported that he was approaching a field to begin the application when the engine made a popping noise and started to vibrate. The airplane slowed and the pilot initiated a turn toward a nearby runway. Since the airplane was still losing speed, the pilot added power, but the vibration increased until the engine lost total power. The airplane impacted terrain and came to rest upside down, resulting in substantial damage to the wings and empennage. The operator reported that the engine was sent to a repair and overhaul facility following the accident. No anomalies were found with the engine that would have precluded normal operation. ## Aircraft - Registration: [N6696K](https://openairdocs.org/aircraft/N6696K), registered now, S/N 426B, built 1978 (OpenAirDocs) - Reported make and model: Grumman G164B - Registry model: [Grumman Acft ENG Cor-Schweizer G-164B](https://openairdocs.org/model/grumman-acft-eng-cor-schweizer-g-164b) (registry code 3952802) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 426B - Year built: 1978 - Airframe hours: 9081 - Engines: Pratt and Whitney R1340 SERIES 600 horsepower reciprocating - Damage: Substantial damage - Flight: Aerial application, Part 137 - Operator: Valley Air Service Ltd - Registered owner: Valley Air Service Ltd - Airworthiness certificate: Special, Restricted (Special) - Last inspection: Annual, December 14, 2017, 50 hours before - Departed: O08, Colusa, CA - Equipment: None ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 41; injuries: none; commercial; airplane ratings: single-engine land; medical: class 2, without waivers/limitations; last flight review February 26, 2018; seat: single; restraint: 3-point; flight hours: 4,380 total, 2,100 in this make and model, 4,207 as pilot in command, 275 in the last 90 days, 75 in the last 30 days, 4 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: 190° at 3 knots - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 82 °F, dew point 46 °F - Altimeter: 30.03 inHg - Observed at: MYV, 20 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 20180709015899A](https://openairdocs.org/incident/20180709015899A), Jul 9, 2018: Grumman Acft Eng Cor-Schweizer G-164B, Colusa, CA, Destroyed. On July 9, 2018, at approximately 11:00 am PST. During several aerial application routes over a rice field approach the pratt-whitney R-1340 powerplant made a… ## Docket (3 files) The files NTSB released with the investigation on June 2, 2021, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=97719. 20.5 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 7 pages, 18.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11915107&FileExtension=pdf&FileName=6120%20FINAL_Redacted-Rel.pdf - Record of conversation - operator (item 2, PDF, 1 page, 123 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11915189&FileExtension=pdf&FileName=ROC%20operator-Rel.pdf - On scene photos - courtesy of the operator (item 3, PDF, 2 pages, 1.8 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=11915034&FileExtension=pdf&FileName=on%20scene%20photos-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.