- Date
- July 24, 2017, 16:00 local (21:00 UTC)
- Place
- Toterville, IA
- Injuries
- 1 uninjured
- Damage
- Substantial damage
- Phase of flight
- Maneuvering
- Aircraft
- N47AHBell 47G 3B
- Defining event
- Maneuvering-low-alt flying: Loss of control in flight
- Weather
- Visual (VMC) · Day
- Status
- Completed · report April 23, 2018
- Report
- Approved by Office Director
- NTSB office
- General Aviation Accidents
- Parties
- FAA
- FAA report
- 20170724020609A
- Case key
- 95655
From the NTSB’s public API. By law, NTSB reports can’t be used as evidence in lawsuits over the accident.
On this page
Probable cause
The pilot’s failure to maintain rotor rpm while maneuvering at low altitude with low airspeed and a tailwind.
Findings · 5
NTSB’s coded findings. Those marked are part of the probable cause; the rest are factors or other findings. Under each, the cases with the same finding.
Sequence of events
The events NTSB coded, in order, by phase of flight. The defining event is the one that best describes the accident. Under each, the cases with the same event anywhere in their sequence.
Analysis
According to the helicopter pilot, during an agricultural flight, he made a downwind turn to spray the intended field. During the low airspeed right turn, he increased the engine power, and the rotor rpm decreased. He reported that he leveled the helicopter to clear power lines, but the rotor rpm remained low. The helicopter descended, and the pilot landed the helicopter in a corn field. The helicopter sustained substantial damage to the tailboom and horizontal stabilizer. The nearest METAR located 15 nautical miles south-southeast from the accident site reported that, about the time of the accident, the wind was calm. The pilot reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.
Factual narrative
According to the helicopter pilot, during an agricultural flight, he made a downwind turn to spray the intended field. During the low airspeed right turn, he increased the engine power and the rotor RPM decreased. He reported that he leveled the helicopter to clear powerline wires, but the rotor RPM remained low. The helicopter descended, and the pilot landed the helicopter in a corn field. The helicopter sustained substantial damage to the tailboom and the horizontal stabilizer. The nearest METAR was 15 nautical miles south-southeast and reported that about the time of the accident, the wind was calm. The pilot reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.
Aircraft
- Registration
- N47AH
- Reported as
- Bell 47G 3B (3B)
- Category
- Helicopter
- Serial number
- 2645
- Built
- 1961
- Airframe hours
- 14,259
- Engine
- Lycoming TV0-435 SER, 250 horsepower, reciprocating
- Damage
- Substantial damage
- Flight
- Aerial application · Part 137
- Operator
- Scotts Helicopter Service Inc
- Registered owner
- Scotts Helicopter Service Inc
- Airworthiness certificate
- Special, Restricted (Special); Standard, Normal
- Last inspection
- Annual · May 1, 2017
- Departed
- Toterville, IA
- Destination
- Toterville, IA
Matched to the registry by N-number and the event date; the registry’s history has gaps, so older matches can be wrong. Compare the reported make and model.
Flight crew
As NTSB recorded them. NTSB leaves out names.
- Role
- Pilot
- Age
- 33
- Injuries
- None
- Certificate
- Private
- Airplane ratings
- Single-engine land
- Medical
- Class 2, Without waivers/limitations
- Last flight review
- April 13, 2017
- Seat
- Left
- Restraint
- 4-point
- Flight hours
- 389 total · 1 in this make and model · 150 in the last 90 days · 100 in the last 30 days · 10 in the last 24 hours
Weather
- Conditions
- Visual (VMC) · Day
- Wind
- Calm
- Visibility
- 7 statute miles
- Lowest ceiling
- None
- Temperature
- 57 °F, dew point 55 °F
- Altimeter
- 30.03 inHg
- Observed at
- KAUM, 15 nm away
Docket · 2
The files NTSB released with the investigation on October 21, 2020, on NTSB’s docket system: statements, records, photos and specialists’ reports. 3.7 MB in all.
FAA reports on this event · 1
The FAA’s own accident and incident reports, matched to the aircraft by N-number and date.
Other investigations on N47AH · 2
Matched to the same aircraft by N-number and date.