Robinson Helicopter Company R44 II accident near Grants, New Mexico, May 10, 2012
On May 10, 2012 at about 4:15 pm local time, a Robinson Helicopter Company R44 II, registered N7523S, was substantially damaged in an accident during maneuvering (low-alt flying) near Grants, New Mexico. It was a ferry 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 engine power due to an excessively rich fuel mixture that occurred during operations at idle power settings at a high density altitude. Contributing to the accident was the flight instructor’s poor decision-making in choosing to practice an unnecessary autorotation over mountainous terrain.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- May 10, 2012 · about 4:15 pm local time
- Place
- Grants, New Mexico · map
- Type
- Accident
- Injuries
- No one was hurt; 2 people were on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson Helicopter Company R44 II
- Registration
- N7523S · no longer on the register · serial 10276
- Damage
- Substantial damage
- Flight
- Ferry flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The helicopter, which had been based at sea level, had recently been sold, and the flight instructor and a commercial pilot were flying it across the country to its new base. While in cruise flight over mountainous terrain at high density altitude, the flight instructor initiated a practice autorotation for the purpose of maintaining proficiency. During the autorotation, the engine stopped producing power. The instructor continued the autorotation to a landing; however, during the landing, the main rotor blades severed the tail boom. A postaccident engine run at high density altitude revealed that the engine ran rough at an idle power setting with a full rich fuel mixture. Leaning the fuel mixture improved engine performance. It is likely that the fuel control unit was set by maintenance personnel to provide a rich mixture at sea level, which resulted in poor engine performance at high density altitudes.
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
- Loss of engine power (total) during maneuvering (low-alt flying) defining event
- Autorotation Off-field or emergency landing
The NTSB's findings
- cause Aircraft › Aircraft power plant › Engine fuel and control › Fuel control/carburetor › Related operating info
- factor Personnel issues › Action/decision › Action › Unneccessary action › Instructor/check pilot
- factor Environmental issues › Physical environment › Terrain › Mountainous/hilly terrain › Ability to respond/compensate
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine land; instructor: helicopter; instructor: instrument helicopter; instrument: helicopter; rotorcraft: helicopter
- Flight time: 613 hours in all; 138 in this make and model; 32 in the last 90 days; 24 in the last 30 days; 529 as pilot in command; 121 on instruments
- Last flight review: May 3, 2011
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: rgt
- Injury: no injuries
Pilot
- Certificate: commercial pilot
- Ratings: rotorcraft: helicopter
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 1,377.3 hours
- Last inspection: annual inspection, April 29, 2012
- Maximum gross weight: 2,400 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-540 SER (piston); 0 hours total
- Operator: Iprerogative, Inc
The flight
- Departed from: KABQ Albuquerque NM at 3:00 pm
- Destination: KPGA Page AZ
- Flight plan: VFR
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 170° at 5 knots
- Sky: clear
- Temperature: 63°F (17°C), dew point 25°F (-4°C)
- Altimeter: 30.05 inHg
- Observation at 3:53 pm from KGNT
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 2 |
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.