FLIGHT FINDINGSAVIATION OCCURRENCE MAP
Back to map

CEN21LA339 · Robinson Helicopter Company R44 II

20 Jul 2021 · West Liberty, IA, United States

Robinson Helicopter Company R44 II · Accident: low altitude operation/event while maneuvering

Report a problem

Event

NTSB case
CEN21LA339
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

Robinson Helicopter Company R44 II

Aircraft type
Robinson R44
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
N983HA
Operator
Unknown
Onboard fatalities
Unknown
Route
From not recordedTo not recorded
Aircraft age
About 17 years (built 2004)
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
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

No findings designated as a cause are recorded in the NTSB data yet.

Approximate · Coordinates as recorded by the NTSB; no uncertainty radius is established.

NTSB narrative

The pilot reported that he was performing an aerial application pass when he felt a “big tug” on the helicopter. The pilot realized he had struck a wire as the helicopter pitched up and started to slow. The helicopter flew about 150 yards when the pilot felt another “huge jerk” on the rear of the helicopter. The helicopter started to spin and rotated about 2-3 times before it impacted the ground and rolled over coming to rest on its left side. On exiting the helicopter, the pilot observed the wire wrapped around the helicopter. It had cut into the tail rotor gearbox “tearing it” off the helicopter. The pilot reported that there were no preaccident mechanical failures or malfunctions with the helicopter that would have precluded normal operations. The pilot reported that prior to conducting the aerial application pass, he circled the field and did not observe any obstructions.

The pilot did not submit the National Transportation Safety Board Pilot/Operator Aircraft Accident/Incident Report Form 6120.1.

Probable cause

The pilot’s failure to see and avoid a wire while maneuvering at low altitude during an aerial application flight, resulting in a collision with the wire.

Verbatim NTSB analysis and probable cause from the NTSB dataset

Sources

NTSB record CEN21LA339
Event ID
20210727103560
Case number
CEN21LA339
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: 4b21dc18993bec7ba6d3f2429d312d8509787a9bc9d5e7c1e615e4e1eb40f66d; retrieved 2026-09-16T14:20:02.925Z.