Amateur-built REVOLUTION MINI 500 accident near Middleboro, Massachusetts, April 7, 2010
On April 7, 2010 at about 8:22 pm local time, a amateur-built REVOLUTION MINI 500 (helicopter), registered N118NR, was substantially damaged in an accident during landing (flare/touchdown) near Middleboro, Massachusetts. 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
A loss of engine coolant, which resulted in a loss of engine power during the pilot’s attempt to cushion a precautionary landing. Contributing to the accident was a disconnected engine coolant hose and the pilot's inadequate preflight inspection.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- April 7, 2010 · about 8:22 pm local time
- Place
- Middleboro, Massachusetts · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Amateur-built REVOLUTION MINI 500
- Registration
- N118NR · no longer on the register · serial 0118
- Damage
- Substantial damage
- Flight
- Personal flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
During a 50-minute flight the helicopter pilot observed the engine coolant temperature and the exhaust gas temperature increase. The pilot attempted a precautionary landing to a field; however, as he was adding power to cushion the landing, the engine lost power due to overheating. The helicopter then landed hard and rolled over. Postflight examination of the helicopter revealed that a coolant hose was disconnected and corrosion was noted on the radiator fins, indicating that leakage had occurred over a period of time. No coolant or coolant residue was found during the engine examination.
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
- Miscellaneous/other during enroute (cruise)
- Loss of engine power (total) during landing (flare/touchdown) defining event
- Hard landing during landing (flare/touchdown)
- Roll over during landing (flare/touchdown)
The NTSB's findings
- cause Aircraft › Fluids/misc hardware › Fluids › Coolant › Fluid level
- factor Personnel issues › Task performance › Inspection › Preflight inspection › Pilot
- factor Aircraft › Fluids/misc hardware › Misc hardware › Hoses and tubes › Not serviced/maintained
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: rotorcraft: helicopter
- Flight time: 526 hours in all; 43 in this make and model; 25 in the last 90 days; 12 in the last 30 days; 149 on instruments
- Last flight review: July 11, 2008
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: ctr
- Injury: no injuries
The aircraft
- Airframe total time: 43 hours
- Last inspection: inspection type not recorded
- Maximum gross weight: 482 lb
- Seats: 1
- Landing gear: fixed
- Engine: Rotax 582 (piston); 0 hours total
The flight
- Departed from: PYM Plymonth MA at 7:00 pm
- Destination: PYM Plymouth MA
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 210° at 12 knots, gusting 24
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 84°F (29°C), dew point 45°F (7°C)
- Altimeter: 29.54 inHg
- Observation at 8:52 pm from TAN, 10 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.