CEN09CA511 · Brantly B-2B
Brantly B-2B · Accident: loss of control in flight during autorotation
From Martinsville, IN to Martinsville, IN
Event
- NTSB case
- CEN09CA511
- 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
Brantly B-2B
- Aircraft type
- Brantly B-2
- 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
- N9023Z
- Operator
- Mcdaniel Mark O
- Onboard fatalities
- Unknown
- Route
- From Martinsville, INTo Martinsville, IN
- Aircraft age
- Not recorded
- 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
- Autorotation
- 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 control in flight
- 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
- Personnel issues › Action/decision
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot was practicing solo 180-degree autorotations in preparation for a private pilot helicopter add-on rating. During the accident autorotation, the helicopter was in a left turn at an altitude of 500 feet above ground level(agl). The helicopter exited the turn "a little low and lost some rotor speed." While attempting to recover the low rotor speed, the pilot had to extend his glide path more than he anticipated due to approaching terrain and obstacles, which in turn slowed the forward airspeed. The pilot reported, "Of course I wish I had abandoned the auto at this point. I flared [the helicopter] but with high density altitude and the out of ground effect of the soybeans, I still entered the thick-drilled soybeans, which piled up on my right skid." The helicopter then rolled over and came to rest on its right side. Examination of the helicopter revealed the main rotor blades were destroyed and the fuselage was buckled. No mechanical anomalies were noted with the helicopter.
Probable cause
The pilot's improper recovery during the autorotation. Contributing to the accident was the pilot's delayed remedial action to abort the practice autorotation.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN09CA511
- Event ID
- 20090810X41334
- Case number
- CEN09CA511
- 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. 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: 6b4cd022ab8328d66dd73fcc4208c125a6746d8584337387264003d5680acf92; retrieved 2026-09-15T12:46:44.304Z.