Brantly Helicopter B-2 accident near Denison, Iowa, July 3, 1985
On July 3, 1985 at about 1:00 am local time, a Brantly Helicopter B-2, registered N6799D, was substantially damaged in an accident near Denison, Iowa (Denison Muni airport). It was a personal flight under general aviation rules (Part 91). 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 NTSB has not yet published a probable cause for this accident. Investigations usually take one to two years; this page updates when the final report is released.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 3, 1985 · about 1:00 am local time
- Place
- Denison, Iowa · Denison Muni · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Brantly Helicopter B-2
- Registration
- N6799D · no longer on the register · serial 19
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
PLT REPORTS THAT THE ENG IDLE SETTING WAS TOO LOW AND THE ENG QUIT WHEN HE REDUCED POWER DURING A PRACTICE AUTOROTATION. THE ACFT TOUCHED DOWN HARD AND THE MAIN ROTOR CONTACTED TAIL BOOM.
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: airline transport pilot, flight instructor, commercial pilot
- Ratings: multi-engine land; single-engine land; instructor: airplane multi-engine; instructor: airplane single-engine; instructor: helicopter; instructor: instrument airplane; rotorcraft: helicopter
- Flight time: 6,591 hours in all; 263 in this make and model; 27 in the last 90 days; 5,686 as pilot in command
- Medical certificate: Class 1 (valid medical--w/ waivers/lim.)
- Seat: left
The aircraft
- Airframe total time: 1,295 hours
- Last inspection: annual inspection, June 25, 1985; 4 hours since
- Maximum gross weight: 1,670 lb
- Seats: 2
- Landing gear: retractable
- Engine: Lycoming VO-360-A1A (piston); 0 hours total
The flight
- Flight plan: none
- Runway 35, 2,200 ft by 200 ft
Weather at the time
- Light: daylight
- Wind: from 360° at 5 knots
- Visibility: 15 statute miles
- Sky: clear
- Temperature: 75°F (24°C), dew point 0°F (-18°C)
- Observation at 7:30 pm
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.