Grumman G-164A accident near Lapwai, Idaho, May 14, 1991
On May 14, 1991 at about 7:30 pm local time, a Grumman G-164A, registered N8792H, was destroyed in an accident near Lapwai, Idaho. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 1 person was seriously injured. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
THE PILOT'S MISJUDGMENT OF AN AERIAL APPLICATION SWATH RUN. FACTORS INCLUDE A DOWNDRAFT CONDITION AND SOFT TERRAIN.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 14, 1991 · about 7:30 pm local time
- Place
- Lapwai, Idaho · map
- Type
- Accident
- Injuries
- 1 person was seriously injured.
- Weather
- visual conditions (good weather)
- Aircraft
- Grumman G-164A · all G-164As on the register
- Registration
- N8792H · no longer on the register · serial 1530
- Damage
- Destroyed
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
THE PILOT STATED THAT HE ENCOUNTERED DOWNDRAFTS AND RAPID SINK AT THE EDGE OF THE FIELD HE WAS PREPARING TO SPRAY DURING AERIAL APPLICATION ACTIVITY. HE ATTEMPTED TO CORRECT, BUT THE MAIN LANDING GEAR TOUCHED THE CROPS AND THE AIRCRAFT TOUCHED DOWN IN THE MUDDY SOIL. THE AIRCRAFT SLID TO A STOP AND STARTED BURNING.
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: single-engine land; instrument: airplane
- Flight time: 2,411 hours in all; 170 in this make and model; 196 in the last 90 days; 75 in the last 30 days; 2,295 as pilot in command
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: unk
The aircraft
- Last inspection: inspection type not recorded; 0 hours since
- Maximum gross weight: 5,300 lb
- Seats: 1
- Landing gear: fixed
- Engine: P&W R-1340-AN1 (piston); 0 hours total
- Fire on the ground
- Operator: Schumacher Agri-Flite, INC
The flight
- Departed from: LWS Lewiston ID at 7:15 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 330° at 7 knots
- Visibility: 30 statute miles
- Sky: overcast at 12,000 ft; scat at 6,500 ft
- Temperature: 61°F (16°C), dew point 39°F (4°C)
- Altimeter: 30.00 inHg
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 N8792H 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.