Amateur-built ROTOWAY EXEC 90 accident near Kalamazoo, Michigan, July 22, 2000
On July 22, 2000 at about 7:35 pm local time, a amateur-built ROTOWAY EXEC 90 (helicopter), registered N1183M, was substantially damaged in an accident near Kalamazoo, Michigan. It was a personal flight under general aviation rules (Part 91). No one was hurt; 2 people were on board or involved. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
the loss of main rotor rpm due to the failure of the top engine mount and the subsequent loss of the main rotor drive belt tension. A factor was the confined area landing zone.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 22, 2000 · about 7:35 pm local time
- Place
- Kalamazoo, Michigan · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built ROTOWAY EXEC 90 ROTOWAY EX
- Registration
- N1183M · registry record · serial J123151
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot reported he was flying his experimental helicopter about 700 feet above ground level in cruise flight when the top motor mount made of cast aluminum broke. He reported that the belt tension to the main rotor was lost and he was unable to maintain rotor rpm. He executed an autorotation to a small back yard surrounded by trees. The helicopter landed hard and the main rotor blades flexed down and chopped off the tailboom.
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: private
- Ratings: rotorcraft: helicopter
- Flight time: 158 hours in all; 158 in this make and model; 21 in the last 90 days; 5 in the last 30 days; 68 as pilot in command
- Medical certificate: Class 3 (valid medical--no waivers/lim.)
- Seat: rgt
The aircraft
- Airframe total time: 175 hours
- Last inspection: annual inspection
- Maximum gross weight: 1,425 lb
- Seats: 2
- Landing gear: fixed
- Engine: Rotorway EXEC 150 (piston); 0 hours total
The flight
- Departed from: 4NO MI at 7:00 pm
- Flight plan: none
- Runway 0
Weather at the time
- Light: daylight
- Wind: from 330° at 8 knots
- Visibility: 10 statute miles
- Sky: broken clouds at 8,000 ft; scat at 3,900 ft
- Temperature: 154°F (68°C), dew point 127°F (53°C)
- Altimeter: 30.00 inHg
- Observation at 5:53 pm from AZO, 10 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Crew | 1 | |||
| Passengers | 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 N1183M 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.