WPR18LA164 · Bell 206 B
Due North Aviation Bell 206 B · Accident: loss of engine power (partial) while maneuvering
From Madison Municipal Airport (IMS) to Bernie's Airport (OA10)
Event
- NTSB case
- WPR18LA164
- Event typeAccident: someone killed or seriously injured, or the aircraft substantially damaged (NTSB definition). Incident: an occurrence that affected or could have affected safety, short of that. Glossary
- Accident
- InvestigationHow far the investigation had got when the record was published: preliminary, ongoing, final or completed. Unknown where the source does not say. Glossary
- Completed
- API-reported fatalities
- 0 · all aircraft and ground
- Ground fatalities
- Unknown
- OperationWhat kind of flying it was, grouped by the rules it flew under: airline (US Part 121), air taxi and commuter (Part 135), general aviation (Part 91 and similar), military or government. Glossary
- General aviation
- WeatherVisual meteorological conditions (VMC): good enough to fly by looking outside. Instrument conditions (IMC): cloud or low visibility, flying by instruments. Glossary
- Visual Meteorological Cond
Bell 206 B
- Aircraft type
- Bell 206
- Category
- Helicopter
- RegistrationThe aircraft's tail number, such as N12345 or G-ABCD. Registrations are reissued, so the same one years apart can be a different aircraft. Glossary
- N518Z
- Operator
- Due North Aviation
- Onboard fatalities
- Unknown
- Route
- From Madison Municipal Airport (IMS), Madison, INTo Bernie's Airport (OA10), Mount Orab, OH
- Aircraft age
- About 31 years (built 1987)
- Flight rulesThe regulations the flight operated under: in the US, Part 91 (general aviation), Part 121 (airlines), Part 135 (air taxi and commuter) and others; for flights abroad, the NTSB's coarser commercial or non-commercial code. Glossary
- Part 91: General Aviation
- Phase of flightThe stage of the flight when things started to go wrong: standing, taxi, takeoff, initial climb, en route, maneuvering, approach or landing. Glossary
- Maneuvering · low-altitude flying
- Defining eventThe single coded event the NTSB judges best describes what happened (records from 2008 on). Older records name the first occurrence in the sequence instead. Glossary
- Loss of engine power (partial)
- DamageDestroyed: beyond practical repair. Substantial: damage that affects the structure, performance or handling and normally needs major repair. Minor: less than that. Glossary
- Substantial
Cause areas
- Not determined › Not determined
Approximate · Coordinates from the NTSB case API, which marks them as estimated or does not say; no uncertainty radius is established.
NTSB narrative
The pilot and observer were conducting a powerline patrol flight in the helicopter. About 40 minutes into the flight, while flying at 35 to 40 knots about 120 ft above ground level, the pilot heard the main rotor losing speed; the low rotor rpm light subsequently illuminated, and the associated aural warning sounded. The pilot entered an autorotation, during which he raised the collective to avoid impacting a set of power transmission lines. The pilot reported that the rotor speed remaining upon reaching the touchdown point was insufficient to cushion the landing, and the helicopter landed hard, resulting in substantial damage. After landing, the pilot noted that the engine was still partially producing power, and he shut it down using the throttle. Examination of the airframe and engine revealed no mechanical malfunctions or component failures that would have precluded normal operation. Based on the available information, the reason for the loss of engine power could not be determined.
Probable cause
A partial loss of engine power for undetermined reasons, and a loss of main rotor rpm during the subsequent autorotation, which resulted in a hard landing.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR18LA164
- Event ID
- 20180605X53732
- Case number
- WPR18LA164
- Dataset
- full-current
- Source SHA-256
- 5cf380f0061817c0331a6b2d8cc7e0ee3a79bea469a1001dc5c10e56f35f5ab3
Source notes (4)
- Unreviewed is an editorial label, not an investigation status. API-sourced is not report-checked or human-reviewed. Explicit event totals are used without summing aircraft injury tables; onboard allocation is withheld. Unknown values remain unknown. The operation category is mapped from the NTSB-reported FAR part and has not been reviewed.
- Filled from the NTSB case API where the bulk record had no value: investigation status, coordinates, cause areas. Values present in the bulk record are kept.
- The date is the local date, which is the same as the UTC date the NTSB stores.
- API snapshot SHA-256: 4f543cf654778f7bc9a4d4d02ea227e4cc4e86c5dcb92f636adb0f0f020c8c63; retrieved 2026-09-16T07:23:11.215Z.