Grumman G164 - B accident near Princeton, California, August 4, 2015
On August 4, 2015 at about 3:30 pm local time, a 1976 Grumman G164 - B, registered N48452, was substantially damaged in an accident during maneuvering (low-alt flying) near Princeton, 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
The loss of engine power during an agricultural application flight due to a cylinder failure.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- August 4, 2015 · about 3:30 pm local time
- Place
- Princeton, California · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Grumman G164 - B B, built 1976 · all G164 - Bs on the register
- Registration
- N48452 · registry record · serial 24B
- 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, during the agricultural spray run, the engine lost power. The airplane was unable to maintain altitude, so the pilot made a forced landing to a rice field. After touchdown, the airplane nosed over, which resulted in substantial damage to the rudder. A postaccident examination of the engine revealed that the No. 2 cylinder head had cracked and lifted under the cooling fins on the cylinder's left side. The crack continued across the top and inside of the head to the intake valve seat, which would have allowed hot gases to enter the induction system and resulted in the subsequent loss of power. A review of the airplane's maintenance records revealed that a mandatory 100-hour repetitive visual inspection of the cylinder had been performed 66.7 flight hours before the accident flight.
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
- Powerplant sys/comp malf/fail during maneuvering (low-alt flying)
- Loss of engine power (partial) during maneuvering (low-alt flying) defining event
- Nose over/nose down during landing (landing roll)
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine (reciprocating) › Recip eng cyl section › Failure
- Environmental issues › Physical environment › Terrain › (general) › Contributed to outcome
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land
- Flight time: 13,000 hours in all; 13,000 in this make and model; 100 in the last 90 days; 40 in the last 30 days; 13,000 as pilot in command
- Last flight review: April 30, 2014
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 16,060 hours
- Last inspection: annual inspection, March 7, 2015; 66 hours since
- Maximum gross weight: 5,431 lb
- Seats: 1
- Landing gear: fixed
- Engine: Pratt & Whitney R-1340 (piston); 11,271 hours total
- Operator: Valley Air Service LTD
The flight
- Departed from: O08 Colusa CA at 3:00 pm
- Destination: O08 Colusa CA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 130° at 7 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 64°F (18°C), dew point 54°F (12°C)
- Altimeter: 29.94 inHg
- Observation at 2:53 pm from MYV, 8 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
6 documents, released by the NTSB on October 30, 2015. 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, 9 pages | View Download |
| 2 | Weather Data | PDF, 1 page | View Download |
| 3 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page | View Download |
| 4 | FAA Inspector's Report | PDF, 1 page | View Download |
| 5 | Maintenance Records | PDF, 2 pages | View Download |
| 6 | FAA Airworthiness Directive 99-11-02 | PDF, 5 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.