WPR13LA087 · Bell OH-58C
Blair Helicopter Service Bell OH-58C · Accident: flight control system malfunction/failure while maneuvering
From Riverdale, CA to Riverdale, CA
Event
- NTSB case
- WPR13LA087
- 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 OH-58C
- Aircraft type
- Bell OH-58
- 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
- N911PT
- Operator
- Blair Helicopter Service
- Onboard fatalities
- Unknown
- Route
- From Riverdale, CATo Riverdale, CA
- 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 137: Agricultural
- 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
- 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
- Flight control system malfunction/failure
- 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 as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot was conducting agricultural spray operations when he experienced a flight control system anomaly that was described as a right rolling tendency. The pilot increased altitude in an effort to return to the operator's base for repairs. The helicopter became progressively difficult to control, continuing to roll right and not fully responding to left cyclic control inputs, and the pilot maneuvered to a nearby company loader to land. However, the right rolling tendency continued and the helicopter subsequently collided with terrain.
Postaccident examination of the flight control assembly revealed that the gas producer throttle control cable, which is routed adjacent to the connecting linkage push-pull tubes, was entwined with the push-pull tubes. A section of the cable appeared to be pinched between the lower mixing lever unit and the tunnel partition wall. Multiple nylon loop cable clamps, used to secure the throttle cable to the vertical tunnel partition, were broken and separated; however, it was not possible to determine whether the observed damage was the result of the wreckage recovery efforts or a preexisting condition.
Probable cause
A flight control malfunction while maneuvering for reasons that could not be determined because it was not possible to establish whether observed damage to the flight control assembly was the result of wreckage recovery efforts or a preexisting condition.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR13LA087
- Event ID
- 20130109X74659
- Case number
- WPR13LA087
- 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: 8187776b4b7b3be3f2c9350e6ce3a8c764c57773a0de1c25403db8555c173f75; retrieved 2026-09-15T20:43:23.111Z.