Grumman G164B accident near Colusa, California, July 9, 2018
On July 9, 2018 at about 6:00 pm local time, a 1978 Grumman G164B, registered N6696K, was substantially damaged in an accident during maneuvering (low-alt flying) near Colusa, California. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). No one was hurt; 1 person was on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
Total loss of engine power for reasons that could not be determined based on the available information.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 9, 2018 · about 6:00 pm local time
- Place
- Colusa, California · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Grumman G164B, built 1978 · all G164Bs on the register
- Registration
- N6696K · registry record · serial 426B
- 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 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.
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 engine power (total) during maneuvering (low-alt flying) defining event
- Nose over/nose down during landing
The NTSB's findings
- Not determined › Not determined › (general) › (general) › Unknown/Not determined
- Aircraft › Aircraft power plant › Engine (reciprocating) › (general) › Unknown/Not determined
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land
- Flight time: 4,380 hours in all; 2,100 in this make and model; 275 in the last 90 days; 75 in the last 30 days; 4,207 as pilot in command
- Last flight review: February 26, 2018
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 9,081 hours
- Last inspection: annual inspection, December 14, 2017; 50 hours since
- Maximum gross weight: 4,500 lb
- Seats: 1
- Landing gear: fixed
- Engine: Pratt And Whitney R1340 SERIES (piston); 8,765 hours total
- Operator: Valley Air Service Ltd
The flight
- Departed from: O08 Colusa CA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 190° at 3 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 82°F (28°C), dew point 46°F (8°C)
- Altimeter: 30.03 inHg
- Observation at 5:53 pm from MYV, 20 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
3 documents, released by the NTSB on June 2, 2021. 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, 7 pages | View Download |
| 2 | Record of Conversation - Operator | PDF, 1 page | View Download |
| 3 | On Scene Photos - Courtesy of the Operator | PDF, 2 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.