WPR18LA214 · Bell 206 B
Northwind Aviation Bell 206 B · Accident: loss of control in flight while maneuvering
From Basin City, WA to Basin City, WA
Event
- NTSB case
- WPR18LA214
- 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
- N607RA
- Operator
- Northwind Aviation
- Onboard fatalities
- Unknown
- Route
- From Basin City, WATo Basin City, WA
- Aircraft age
- About 47 years (built 1971)
- 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 · 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 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
- Destroyed
Cause areas
- Aircraft › Aircraft oper/perf/capability
- Personnel issues › Action/decision
- Personnel issues › Task performance
Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.
NTSB narrative
The pilot had completed agricultural spray applications in the helicopter and was flying a "rinse-load" to clean the product hopper tank. The wind was from the southeast about 3-5 knots. The pilot reported that he conducted a brief spray run about 50 mph and then applied left pedal input and slightly lowered the collective control to assist him in looking to his left to view the spray pattern; the helicopter immediately began "shaking" and turning rapidly to the left. The pilot pulled up on the collective control and applied right pedal to stop the left yaw. The helicopter continued to "shudder," and the pilot noticed that the helicopter was at a low airspeed and descending. He attempted to regain airspeed, and when the helicopter was about 5 to 10 ft above the ground, he attempted to level the helicopter before the skids contacted the ground. The helicopter impacted the ground and caught fire immediately; a significant portion of the helicopter was destroyed or damaged by the fire.
Postaccident examination of the remaining wreckage did not reveal any preimpact mechanical malfunctions or failures that would have precluded normal operation. The pilot's event description, combined with the benign weather and lack of any physical evidence of mechanical failure, suggest that the accident was pilot induced. When the pilot simultaneously climbed and slowed the helicopter, he also initiated a left yaw by applying left antitorque pedal. That left yaw was amplified when the pilot lowered the collective. At this point, the helicopter was still decelerating, which resulted in airflow changes across the rotor disc, a loss of translational lift, and the beginning stages of vortex ring state, which likely caused buffeting that the pilot reported as a "shudder." Increasing the collective to stop the left yaw also likely increased the stalled area of the rotor disc, strengthening the vortex ring, decreasing rotor efficiency, and increasing descent rate. Because of the helicopter's low altitude, there was insufficient ground clearance for recovery before ground contact.
Probable cause
The pilot's improper execution of a slowing and turning maneuver, which resulted in a loss of control at an altitude that was too low for recovery.
Verbatim NTSB analysis and probable cause from the NTSB dataset
Sources
NTSB record WPR18LA214
- Event ID
- 20180809X30025
- Case number
- WPR18LA214
- 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: 8a4862a9ab5a92d4feccd0925ffa6019272c79a7f95c1a5e2fd547145dedf7b2; retrieved 2026-09-16T08:04:05.743Z.