Robinson R22 accident near Sterling City, Texas, June 17, 2018
On June 17, 2018, a 2004 Robinson R22 (helicopter), registered N410MM, was substantially damaged in an accident during standing (engine(s) operating) near Sterling City, Texas. It was a business 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 pilot’s improper decision to exit the helicopter without shutting down the engine, which allowed the collective/throttle to increase and resulted in a loss of control of the unattended helicopter.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 17, 2018
- Place
- Sterling City, Texas · map
- Type
- Accident
- Injuries
- No one was hurt; 1 person was on board or involved.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson R22 BETA, built 2004 · all R22s on the register
- Registration
- N410MM · no longer on the register · serial 3599
- Damage
- Substantial damage
- Flight
- Business flight · general aviation rules (Part 91)
The NTSB's narrative final · quoted from the NTSB record
The pilot exited the helicopter with the engine set to idle power. Subsequently, the collective/throttle increased due to the engine vibrations, and the helicopter became light on the skids. The helicopter rocked back on the tail, which separated the tail rotor from the helicopter and damaged the main rotor blades. The manufacturer had previously issued a safety notice, which stated to never exit the helicopter unattended with the engine running and the rotors turning because the collective can "creep up, increasing both pitch and throttle, allowing the helicopter to lift off or roll out of control," as occurred in this accident.
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 standing (engine(s) operating) defining event
- Loss of control on ground during standing (engine(s) operating)
- Part(s) separation from AC during standing (engine(s) operating)
The NTSB's findings
- cause Personnel issues › Task performance › Use of equip/info › Use of policy/procedure › Pilot
- cause Personnel issues › Action/decision › Action › Forgotten action/omission › Pilot
- cause Personnel issues › Action/decision › Info processing/decision › Decision making/judgment › Pilot
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › (general) › Not attained/maintained
Pilot
- Certificate: commercial pilot
- Ratings: instructor: helicopter; rotorcraft: helicopter
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: none
- Injury: no injuries
The aircraft
- Maximum gross weight: 1,369 lb
- Landing gear: fixed
- Engine: Lycoming O-360 SERIES (piston); 0 hours total
- Operator: Concho Aviation Llc
The flight
- Departed from: Sterling City TX
- Destination: Sterling City TX
Weather at the time
- Light: daylight
- Temperature: 0°F (-18°C), dew point 0°F (-18°C)
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
2 documents, released by the NTSB on September 27, 2018. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Record of Conversation | PDF, 1 page | View Download |
| 2 | Robinson Helicopter Safety Notice | PDF, 1 page | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
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.