Robinson Helicopter Company R44 II accident near West Liberty, Iowa, July 20, 2021
On July 20, 2021 at about 10:20 pm local time, a 2004 Robinson Helicopter Company R44 II, registered N983HA, was substantially damaged in an accident during maneuvering (low-alt flying) near West Liberty, Iowa. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
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.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 20, 2021 · about 10:20 pm local time
- Place
- West Liberty, Iowa · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson Helicopter Company R44 II, built 2004
- Registration
- N983HA · no longer on the register · serial 10464
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
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.
The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.
The factual record from the NTSB's investigation tables, in plain English
What happened, in order
- Part(s) separation from AC during maneuvering (low-alt flying)
- Loss of control in flight during maneuvering (low-alt flying)
- Low altitude operation/event during maneuvering (low-alt flying) defining event
The NTSB's findings
- Personnel issues › Psychological › Attention/monitoring › Monitoring environment › Pilot
Pilot
- Certificate: commercial pilot
- Ratings: single-engine land; instructor: helicopter; rotorcraft: helicopter
- Flight time: 1 hours in all; 1 in this make and model
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: unk
- Injury: minor injuries
The aircraft
- Last inspection: inspection type not recorded
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-540-AE1A5 (piston); 0 hours total
The flight
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 300° at 5 knots
- Visibility: 10 statute miles
- Sky: clear
- Temperature: 86°F (30°C), dew point 70°F (21°C)
- Altimeter: 30.06 inHg
- Observation at 5:15 pm from KMUT, 13 miles away
Weather report (METAR): KMUT 202215Z AUTO 30005KT 10SM CLR 30/21 A3006 RMK AO2
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
2 documents, released by the NTSB on January 5, 2022. View them here, or download them; the NTSB redacts some personal details before release, and this site shows the NTSB's own titles rather than its file names.
| # | Document | What it is | |
|---|---|---|---|
| 1 | Record of Memorandum - Pilot Statement with on Scene Photos | PDF, 5 pages | View Download |
| 2 | Record of Memorandum - NTSB Pilot/operator 6120.1 Form | PDF, 1 page | View Download |
The same docket at the NTSB · documents without a copy here are fetched from the NTSB when you open them.
Everything on this page comes from the NTSB's public records. The narrative, probable cause and findings are the NTSB's own words; the coded tables behind the report are written out in plain English, with pilots' ages, home towns and medical details left out. The documents and photographs are the NTSB's docket, shown as the NTSB released them. This site's own text never names anyone involved. A preliminary report can change; the final report usually follows one to two years later, and the page is refreshed when it does.