Probable cause
The pilot's failure to maintain clearance with the rotating rotor blades after he exited the helicopter after landing.
NTSB analysis
A witness heard the engine running rough when the agricultural application helicopter took off, adjacent to the field that was going to be sprayed. The pilot then landed the helicopter in the field which had tall vegetation and uneven terrain. The left skid separated during landing resulting in the helicopter resting left side low. The pilot then exited and walked around the helicopter when he was struck by the rotating main rotor blades and was fatally injuried. Examination of the engine revealed an exhaust valve that displayed excessive wear which would result in the engine running rough due to the valve sticking. Logbook records show that the engine and parts manufacturer approval (PMA) manufacturer's recommended maintenance had not been performed.
Text from the NTSB. Open the NTSB docket for CHI08LA211 for the full record.
Event
- Date
- Jul 24, 2008
- Type
- Accident
- Place
- Mayville, Wisconsin
- Highest injury
- Fatal
- Fatal injuries
- 1
- Weather
- Visual (VMC)
- Light
- Day
Bell 47G-4A
- N-number
- N24HM
- Category
- Helicopter
- Damage
- Minor
- Operating rule
- Part 137 (agricultural)
- Purpose of flight
- Aerial application
Other records under this N-number
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.