Grumman Aircraft G-164A accident near Hazelton, Idaho, May 28, 2011
On May 28, 2011 at about 2:00 pm local time, a Grumman Aircraft G-164A, registered N9724, was substantially damaged in an accident during maneuvering (low-alt flying) near Hazelton, Idaho (Hazelton airport). 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
A total loss of engine power during low-level maneuvering due to an excessively worn carburetor.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 28, 2011 · about 2:00 pm local time
- Place
- Hazelton, Idaho · Hazelton · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Grumman Aircraft G-164A
- Registration
- N9724 · no longer on the register · serial 1244
- 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 completing an aerial application pass over a field when the engine began to lose power. He initiated a climb, heard a bang, and observed a white puff of smoke issuing from the top of the engine. The engine subsequently lost all power, and the airplane sustained substantial damage during a forced landing into a pasture. Postaccident examination of the engine revealed that it did not exhibit catastrophic internal damage or any preimpact anomalies that would have precluded normal operation. The carburetor was undamaged during the accident and was subsequently installed on an exemplar engine for testing. During the tests, the engine sputtered, backfired, hesitated, and produced puffs of white smoke from the exhaust ports when the throttle was advanced from idle to power. The sputtering stopped when the throttle was advanced slowly. Examination and disassembly of the carburetor revealed excessive wear, particularly to the accelerator pump assembly. The accelerator pump provides increased fuel flow to the engine during rapid throttle advance, and an ineffective pump would cause engine hesitation and stumbling during acceleration. The symptoms reported by the pilot during what would have been rapid engine acceleration after completing a pass was consistent with a worn accelerator pump, and matched the engine characteristics observed during the carburetor test. The carburetor had been installed on another engine since its most recent maintenance event and its total time since overhaul could not be determined. The engine examination also revealed that five teeth from an intermediate gear within the supercharger drivetrain were fractured, with loading opposite of the direction of rotation. Metallurgical tests found that the teeth failed in overload. Given the rotational speeds of the supercharger system, the gear failure was most likely caused by the sudden engine stoppage after the propeller made contact with the ground.
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
- Off-field or emergency landing during emergency descent
- Collision with terrain or object (not controlled flight into terrain) during landing (flare/touchdown)
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine fuel and control › Fuel control/carburetor › Malfunction
- cause Personnel issues › Task performance › Maintenance › Scheduled/routine maintenance › Not specified
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; single-engine sea; instrument: airplane
- Flight time: 2,964 hours in all; 2,937 in this make and model; 77 in the last 90 days; 25 in the last 30 days
- Last flight review: August 12, 2009
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: sngl
- Injury: no injuries
The aircraft
- Airframe total time: 15,789 hours
- Last inspection: 100-hour inspection, March 30, 2011; 15 hours since
- Maximum gross weight: 7,200 lb
- Seats: 1
- Landing gear: fixed
- Engine: Pratt And Whitney R1340 S3H1G (piston); 0 hours total
- Operator: Crop Jet Aviation LLC
The flight
- Departed from: U94 Hazelton ID at 1:40 pm
- Destination: Hazleton ID
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 210° at 6 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 1,100 ft
- Temperature: 43°F (6°C), dew point 37°F (3°C)
- Altimeter: 29.85 inHg
- Observation at 1:53 pm from BYI, 16 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight 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.