Grumman G164 accident near Lincoln, California, June 4, 2020
On June 4, 2020 at about 1:00 pm local time, a 1982 Grumman G164, registered N8486K, was substantially damaged in an accident during takeoff near Lincoln, California. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s loss of directional control on takeoff for undetermined reasons.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 4, 2020 · about 1:00 pm local time
- Place
- Lincoln, California · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Grumman G164 B, built 1982 · all G164s on the register
- Registration
- N8486K · registry record · serial 709B
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
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.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Loss of control on ground during takeoff defining event
The NTSB's findings
- cause Not determined › Not determined › (general) › (general) › Unknown/Not determined
- Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Directional control › Not attained/maintained
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land
- Flight time: 4,171 hours in all; 2,106 in this make and model; 233 in the last 90 days; 78 in the last 30 days; 3,944 as pilot in command
- Last flight review: July 1, 2019
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: sngl
- Injury: minor injuries
The aircraft
- Airframe total time: 13,392 hours
- Last inspection: 100-hour inspection, June 2, 2020; 2 hours since
- Maximum gross weight: 7,020 lb
- Seats: 1
- Landing gear: fixed
- Engine: Pratt & Whitney PT6-34AG (turboprop); 2,774 hours total
The flight
- Departed from: Lincoln CA at 1:00 pm
- Destination: Lincoln CA
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 59°F (15°C), dew point 54°F (12°C)
- Altimeter: 29.78 inHg
- Observation at 12:55 pm from LHM, 6 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
5 documents, released by the NTSB on June 9, 2022. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 10 pages | View Download |
| 2 | Maps or Charts of Accident Area | PDF, 2 pages | View Download |
| 3 | Brake Examination Report | PDF, 1 page | View Download |
| 4 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page | View Download |
| 5 | Photos | PDF, 4 pages | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.