Grumman-Schweizer G-164B accident near Weiser, Idaho, July 6, 2002
On July 6, 2002 at about 2:45 pm local time, a Grumman-Schweizer G-164B, registered N8440K, was substantially damaged in an accident near Weiser, Idaho. 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 fracture of the number 3 cylinder exhaust pushrod resulting in the exhaust valve's inability to open during the exhaust cycle and the subsequent engine stoppage. Contributing factors were the ditch and elevated roadway which the aircraft crossed during the gear collapse.
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 2:45 pm local time
- Place
- Weiser, Idaho · 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
- N8440K · no longer on the register · serial 694B
- 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 of the "Agcat" cropduster had just taken off and was making his first spray run over a field when the Pratt & Whitney R-1340 engine began to run rough. He pulled up and executed a right turn away from obstacles crossing the Snake River during which the engine abruptly stopped. The pilot rolled out and executed a forced landing in a beet field during which the aircraft crossed an elevated dirt/gravel roadway bounded on its north and south edges by a shallow ditch, and the aircraft's landing gear separated from the airframe. The aircraft then nosed over and came to a stop. The engine, which had been overhauled and inspected 81 and 31 hours respectively, was examined. The examination revealed that the number 3 cylinder exhaust valve steel pushrod was broken near the rocker arm end of the rod and the rod displayed very slight bending deformation. The separation surfaces of the broken rod end were observed to be mechanically battered. Removal or separation of the exhaust pushrod results in the exhaust valve's inability to open during the exhaust phase cycle for the associated cylinder, and can result in hot exhaust from the cylinder back-flowing out the intake valve when it opens during the intake cycle.
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: commercial pilot
- Ratings: multi-engine land; single-engine land
- Flight time: 17,174 hours in all; 10,629 in this make and model; 136 in the last 90 days; 60 in the last 30 days; 16,686 as pilot in command
- Last flight review: March 8, 2002
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: frt
- Injury: no injuries
The aircraft
- Airframe total time: 7,384 hours
- Last inspection: 100-hour inspection, May 22, 2002; 31 hours since
- Maximum gross weight: 6,800 lb
- Seats: 1
- Landing gear: fixed
- Engine: Pratt & Whitney R-1340-S3H1G (piston); 0 hours total
The flight
- Departed from: S87 Weiser ID at 2:40 pm
- Flight plan: none
Weather at the time
- Light: daylight
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 66°F (19°C), dew point 48°F (9°C)
- Altimeter: 29.96 inHg
- Observation at 2:55 pm from EUL, 38 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.
Other NTSB records under N8440K the same tail number, which may have belonged to a different aircraft at the time
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.