Grumman-Schweizer G-164B accident near Sacramento, California, July 6, 2002
On July 6, 2002 at about 4:30 pm local time, a Grumman-Schweizer G-164B, registered N3631B, was substantially damaged in an accident near Sacramento, 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
Propeller blade failure due to fatigue. A contributing factor was the rising embankment.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 6, 2002 · about 4:30 pm local time
- Place
- Sacramento, California · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Grumman-Schweizer G-164B
- Registration
- N3631B · no longer on the register · serial 762B
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
After taking off and initiating a left turn at an altitude of approximately 15 feet agl, the pilot heard a "loud bang and a sharp jolt as the airplane began shaking violently." The pilot leveled the wings and reduced power; however, the vibration did not subside. He then initiated a shallow right turn in order to land on a road. "As I began to maneuver for landing I saw a burst of flame from the exhaust and heard the engine quit and felt the aircraft settle." The airplane impacted a levee and flipped over, coming to rest inverted. During post-accident investigation of the wreckage, it was noted that the outboard section of one propeller blade was missing. The inboard section of the Hamilton Standard propeller blade was sent to the NTSB Materials Laboratory Division for examination. It was reported that the blade was fractured approximately 26 to 27 inches from the butt end. Optical examination of the fracture face found features consistent with fatigue progression over the majority of the fracture. Closer examinations revealed beach marks and other progression features indicating fatigue initiation at a mechanical dent on the camber surface near midspan. Further examination indicated that fatigue accounted for approximately 70% of the total fracture area.
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
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane single-engine; instrument: airplane
- Flight time: 8,100 hours in all; 4,500 in this make and model; 350 in the last 90 days; 150 in the last 30 days; 8,044 as pilot in command; 900 on instruments
- Last flight review: December 18, 2001
- Medical certificate: Class 2 (valid medical--no waivers/lim.)
- Seat: ctr
- Injury: no injuries
The aircraft
- Airframe total time: 10,600 hours
- Last inspection: annual inspection, June 1, 2002; 95 hours since
- Maximum gross weight: 3,400 lb
- Seats: 1
- Landing gear: fixed
- Engine: Pratt & Whitney R-1340 AN-1 (piston); 0 hours total
The flight
- Departed from: Sacramento CA at 4:28 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: at 3 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 70°F (21°C), dew point 52°F (11°C)
- Altimeter: 29.92 inHg
- Observation at 4:53 pm from SMF, 5 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
The docket, the folder of records gathered during an investigation (maintenance records, photographs, witness statements, examinations), has not been read from the NTSB for this case yet; the list appears here once it has. Open the docket at the NTSB.
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.