Probable cause
The helicopter flight instructor's delayed remedial action during an autorotation resulting in a loss of control and impact with terrain.
NTSB analysis
According to the flight instructor, while performing a simulated, right turn, 180 degree autorotation the helicopter impacted the ground and rolled over. The flight instructor stated that at 200 feet AGL, the low rotor RPM horn sounded, and he and the student pilot "attempted a recovery." The flight instructor reported that after hearing the low rotor RPM horn, but prior to impact, "a loud thumping noise could be heard and a violent shake in the cyclic could be felt." He stated that he chose to level the helicopter before it impacted the terrain and rolled. The helicopter sustained substantial damage to the main rotor system, fuselage and tail boom.
The pilot reported that there were no mechanical failures or anomalies prior to flight that would have prevented normal operation.
Text from the NTSB. Open the NTSB docket for GAA15CA224 for the full record.
Event
- Date
- Aug 13, 2015
- Type
- Accident
- Place
- Caldwell, Idaho
- Nearest airport
- Caldwell Industrial (EUL)
- Highest injury
- Minor
- Minor injuries
- 2
- Weather
- Visual (VMC)
- Light
- Day
Robinson Helicopter R22 BETA
- N-number
- N3103Q
- Category
- Helicopter
- Year built
- 2006
- Damage
- Substantial
- Operating rule
- Part 91 (general aviation)
- Purpose of flight
- Instructional
From the NTSB aviation accident database: N-registered aircraft, events since 2008, data through Oct 28, 2026. The file is published monthly, so the latest weeks are incomplete and recent records can change. The official source is the NTSB aviation investigation search. CheckAero is independent and not affiliated with the NTSB.