Bell 47G3B1 accident near Lasalle, Minnesota, June 11, 1991
On June 11, 1991 at about 8:30 pm local time, a Bell 47G3B1 (helicopter), registered N73284, was substantially damaged in an accident near Lasalle, Minnesota. 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 PILOT'S FAILURE TO MAINTAIN ADEQUATE CLEARANCE FROM THE TERRAIN. A RELATED FACTOR IS THE PILOT'S MISJUDGED ALTITUDE ABOVE THE CROP.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 11, 1991 · about 8:30 pm local time
- Place
- Lasalle, Minnesota · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Bell 47G3B1 · all 47G3B1s on the register
- Registration
- N73284 · no longer on the register · serial 2908
- 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 STATED THAT HE WAS PERFORMING AERIAL APPLICATION OPERATIONS OVER A WHEAT FIELD WHEN THE ACCIDENT OCCURRED. HE WAS FLYING HIS FIRST SPRAY SWATH ON THE FIELD WHEN THE SPRAY BOOM CONTACTED THE CROP. THE HELICOPTER IMPACTED THE GROUND AND CAME TO REST INVERTED. THE PILOT'S RECOMMENDATION WAS TO FLY HIS SPRAY SWATHS AT A HIGHER ALTITUDE.
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; rotorcraft: helicopter
- Flight time: 2,320 hours in all; 50 in this make and model; 68 in the last 90 days; 66 in the last 30 days; 2,175 as pilot in command
- Medical certificate: Class 2 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 9,016 hours
- Last inspection: annual inspection, April 1, 1991; 68 hours since
- Maximum gross weight: 2,950 lb
- Seats: 3
- Landing gear: fixed
- Engine: Allison 250-C20 (turboshaft); 0 hours total
- Operator: Tery Jon Aviation
The flight
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 170° at 2 knots
- Visibility: 20 statute miles
- Sky: clear
- Temperature: 81°F (27°C), dew point 0°F (-18°C)
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 N73284 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.