# NTSB WPR20LA175: Grumman G164, N8486K, Lincoln, CA, June 4, 2020 - Type: NTSB accident investigation - Classification: Accident · Minor injuries · Class 3 · Limited · Final report - Date: June 4, 2020, 06:00 local (13:00 UTC) - Place: Lincoln, CA - Coordinates: 38.923053, -121.470832 - Nearby events: https://openairdocs.org/map.md?lat=38.9231&lon=-121.4708&mi=10 - Phase of flight: [Takeoff](https://openairdocs.org/ntsb-phases/300) (OpenAirDocs' grouping) - Defining event: [Takeoff: Loss of control on ground](https://openairdocs.org/ntsb-events/230) - Highest injury: Minor injuries - Injuries: 1 minor - Status: Completed - Report: Approved by Office Director - Investigation class: Class 3 - NTSB office: Western Pacific Region - Parties: Federal Aviation Administration - NTSB case key (mKey): 101421 - NTSB case page: https://web.ntsb.gov/investigations/?ntsbnumber=WPR20LA175 - NTSB report (PDF, downloads): https://data.ntsb.gov/carol-repgen/api/Aviation/ReportMain/GenerateNewestReport/101421/pdf - NTSB docket: https://data.ntsb.gov/Docket?ProjectID=101421 - Page: https://openairdocs.org/ntsb/WPR20LA175 ## Probable cause The pilot’s loss of directional control on takeoff for undetermined reasons. ## 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: [Schweizer G-164B, 7 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md?model=8059055), [All aircraft, 2,247 cases](https://openairdocs.org/ntsb-findings/05000000/cases.md) - [Performance/control parameters: directional control](https://openairdocs.org/ntsb-findings/01062020): Aircraft › Aircraft oper/perf/capability · Not attained/maintained (probable cause); cases with it: [Schweizer G-164B, 6 cases](https://openairdocs.org/ntsb-findings/01062020/cases.md?model=8059055), [All aircraft, 3,958 cases](https://openairdocs.org/ntsb-findings/01062020/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 control on ground](https://openairdocs.org/ntsb-events/230) (defining event); cases with it: [Schweizer G-164B, 8 cases](https://openairdocs.org/ntsb-events/230/sequence.md?model=8059055), [All aircraft, 4,585 cases](https://openairdocs.org/ntsb-events/230/sequence.md) ## Analysis The pilot reported that on takeoff roll, he felt the left brake lock up, which pulled the airplane hard to the left off the runway. The airplane came to rest inverted. All four wing panels and the empennage were substantially damaged. A postaccident examination of the brake system revealed no mechanical anomalies that would have precluded normal operation. The reason for the pilot's loss of directional control of the airplane on takeoff roll was not able to be determined during the investigation. ## Factual narrative On June 4, 2020, about 0600 Pacific daylight time, a Schweizer Aircraft Corp G-164B, N8486K, was substantially damaged when it was involved in an accident near Lincoln, California. The pilot sustained a minor injury. The airplane was operated as a Title 14 Code of Federal Regulations Part 137 agricultural flight. The pilot stated that on the takeoff roll, as soon as the tailwheel started to lift off the ground, he felt the left brake lock up, which pulled the airplane hard to the left. He corrected with full right rudder, after which the airplane straightened out, but the left brake locked up again. The pilot pulled the stick back to see if he could get the airplane flying; however, he did not have enough airspeed to keep the airplane airborne. The airplane barely made it off the east side of the runway before it touched down in a flooded rice field. When the main gear sunk into the mud, the airplane flipped over on its back, which resulted in substantial damage to all four wing panels and the empennage. The pilot successfully evacuated the airplane through the left door with a minor injury. The wind in the area at the time of the accident was reported as calm. A postaccident examination of the airplane's brake system was performed by a licensed Federal Aviation Administration airframe and powerplant mechanic. The mechanic reported that while rotating the left wheel with the brake off, and then with brake pressure applied, the brake system operated normally, with no anomalies noted. The mechanic also reported that his examination failed to reveal any irregularities in the brake master cylinder, the brake cylinders, or any brake lines or fittings in the airplane's left brake. ## Aircraft - Registration: [N8486K](https://openairdocs.org/aircraft/N8486K), registered now, S/N 709B, built 1982 (OpenAirDocs) - Reported make and model: Grumman G164 (B) - Registry model: [Schweizer G-164B](https://openairdocs.org/model/schweizer-g-164b) (registry code 8059055) (OpenAirDocs) - Registry engine: [Pratt & Whitney R1340 series](https://openairdocs.org/engine/pratt-whitney-r1340-series) (registry code 52016, reciprocating) (OpenAirDocs) - Category: Airplane - Serial number: 709B - Year built: 1982 - Airframe hours: 13392 - Engines: Pratt & Whitney PT6-34AG 1200 horsepower turbo prop - Damage: Substantial damage - Flight: Aerial application, Part 137 - Airworthiness certificate: Special, Restricted (Special) - Last inspection: 100 hour, June 2, 2020, 2 hours before - Departed: Lincoln, CA - Destination: Lincoln, CA - Equipment: Stall warning system ## Flight crew As NTSB recorded them. NTSB leaves out names. - Pilot; age 29; injuries: minor; commercial; airplane ratings: single-engine land; medical: class 2, without waivers/limitations; last flight review July 1, 2019; seat: single; restraint: 4-point; flight hours: 4,171 total, 2,106 in this make and model, 3,944 as pilot in command, 233 in the last 90 days, 78 in the last 30 days, 9 in the last 24 hours ## Weather - Conditions: Visual (VMC), Day - Wind: calm - Visibility: 10 statute miles - Lowest ceiling: none - Temperature: 59 °F, dew point 54 °F - Altimeter: 29.78 inHg - Observed at: LHM, 6 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 20200604008709A](https://openairdocs.org/incident/20200604008709A), Jun 4, 2020: Schweizer Aircraft Corp G-164B, Lincoln, CA, Destroyed. On 6/4/2020, the pilot attempted to takeoff from a dirt runway. The pilot started the takeoff roll and the tail started to lift off the ground when the pilot… ## Docket (5 files) The files NTSB released with the investigation on June 9, 2022, on NTSB's docket system: https://data.ntsb.gov/Docket?ProjectID=101421. 12.3 MB in all. - Pilot/operator aircraft accident report, NTSB form 6120.1 (item 1, PDF, 10 pages, 8.6 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9851994&FileExtension=pdf&FileName=Pilot-Operator%20accident%20report%20form_redacted-Rel.pdf - Maps or charts of accident area (item 2, PDF, 2 pages, 1.2 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9852378&FileExtension=pdf&FileName=Accident%20site%20maps-Rel.pdf - Brake examination report (item 3, PDF, 1 page, 182 KB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9852003&FileExtension=pdf&FileName=brake%20examination%20report_redacted-Rel.pdf - Release of aircraft wreckage, NTSB form 6120.15 (item 4, PDF, 1 page, 1.3 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=9852221&FileExtension=pdf&FileName=NTSB%20Release%20of%20Wreckage_recacted-Rel.pdf - Photos (item 5, PDF, 4 pages, 1.0 MB): https://data.ntsb.gov/Docket/Document/docBLOB?ID=13993320&FileExtension=pdf&FileName=Photo%20array%20of%20accident%20site-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.