CEN11LA646 · Bell 206B
Bell 206B · Accident: low altitude operation/event while maneuvering
From Austin Air Ranch Airport (88R) to Austin Air Ranch Airport (88R)
Event
- NTSB case
- CEN11LA646
- 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 206B
- 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
- N3181J
- Operator
- Unknown
- Onboard fatalities
- Unknown
- Route
- From Austin Air Ranch Airport (88R), Spicewood, TXTo Austin Air Ranch Airport (88R), Spicewood, TX
- 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
- 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
- Low altitude operation/event
- 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
- Aircraft › Aircraft oper/perf/capability
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
While maneuvering the helicopter at an altitude of about 400 feet above ground level, the pilot heard the low rotor aural warning in his headset and observed that the rotor speed gauge was reading about 80 percent and decreasing. He lowered the collective, initiated a left turn, and began an autorotative descent to hilly terrain that contained trees and power lines. During the autorotation, the pilot attempted to avoid the power lines, and the helicopter impacted terrain. Although the pilot reported that he believed the engine lost power, a postaccident examination of the helicopter revealed no evidence of any preimpact mechanical failures or malfunctions. Additionally, the helicopter’s engine was run in a test cell for 1 hour 50 minutes with no anomalies detected.
Probable cause
The pilot did not maintain adequate rotor rpm during a low-altitude maneuvering flight.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record CEN11LA646
- Event ID
- 20110916X44706
- Case number
- CEN11LA646
- 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: 4f09095d9c5d9a9073c83cb25c0cd1058db328af8a411e33a4561afbab05766e; retrieved 2026-09-15T16:44:44.694Z.