Robinson Helicopter Company R44 II accident near Princeton, Kentucky, July 16, 2021
On July 16, 2021 at about 5:20 pm local time, a 2006 Robinson Helicopter Company R44 II, registered N512RT, was substantially damaged in an accident during maneuvering (low-alt flying) near Princeton, Kentucky. It was an aerial application (crop spraying) flight under agricultural flying rules (Part 137). 1 person was seriously injured and 1 person had minor injuries. The weather was visual conditions (good weather).
The NTSB's probable cause their words, unchanged
The pilot’s inadequate preflight planning in that he failed to accurately determine the takeoff weight of the helicopter, which resulted in exceeding the helicopter’s maximum weight capability.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- July 16, 2021 · about 5:20 pm local time
- Place
- Princeton, Kentucky · map
- Type
- Accident
- Injuries
- 1 person was seriously injured and 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson Helicopter Company R44 II NO SERIES, built 2006
- Registration
- N512RT · registry record · serial 11465
- Damage
- Substantial damage
- Flight
- Aerial application (crop spraying) flight · agricultural flying rules (Part 137)
The NTSB's narrative final · quoted from the NTSB record
Before takeoff to spray a nearby cornfield, the helicopter was filled with about 50 gallons of spraying solution and a passenger was onboard to assist the pilot with the navigation system. According to the pilot, shortly after takeoff, the low rotor rpm warning light illuminated, and the helicopter “just wouldn’t fly.” The pilot was unable to stay aloft and made a hard landing in a field. An examination of the helicopter revealed substantial damage to the airframe and partial separation of the tail boom. Examination of the engine and its components revealed no anomalies that would have resulted in a loss of power. The helicopter’s estimated takeoff weight was 2,641.4 lbs., which was 141.4 lbs. over its maximum gross weight of 2,500 lbs. After the accident, the pilot told his spouse that he knew the helicopter was “barely overweight but felt it would be fine.” Given that no mechanical anomalies were found, it is likely that the loss of rotor rpm was the result of operating the helicopter in an overweight condition.
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
- Collision with terrain or object (not controlled flight into terrain) during maneuvering (low-alt flying) defining event
- Preflight or dispatch event during prior to flight
The NTSB's findings
- Personnel issues › Task performance › Planning/preparation › Weight/balance calculations › Pilot
- Aircraft › Aircraft oper/perf/capability › Aircraft capability › Maximum weight › Capability exceeded
Pilot
- Certificate: commercial pilot
- Ratings: multi-engine land; single-engine land; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 10,558 hours in all; 104 in this make and model; 39 in the last 90 days; 11 in the last 30 days; 10,378 as pilot in command
- Last flight review: November 3, 2020
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: rgt
- Injury: serious injuries
Pilot-Rated Passenger
- Ratings: single-engine land
- Medical certificate: Class 2 (with waivers/limitations)
- Seat: left
- Injury: no injuries
The aircraft
- Airframe total time: 2,645 hours
- Last inspection: annual inspection, October 1, 2020; 52.5 hours since
- Maximum gross weight: 2,500 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-540-AE1A5 (piston); 2,697 hours total
- Operator: Tomkat Aviation LLC
The flight
- Flight plan: none
- A second pilot was aboard
Weather at the time
- Light: daylight
- Wind: from 200° at 9 knots
- Visibility: 10 statute miles
- Sky: a few clouds at 4,300 ft
- Temperature: 84°F (29°C), dew point 73°F (23°C)
- Altimeter: 30.09 inHg
- Observation at 10:53 am from BWG, 15 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 | |||
| Passengers | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
7 documents, released by the NTSB on July 26, 2023. 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 | Pilot/operator Aircraft Accident Report, NTSB Form 6120.1 | PDF, 11 pages | View Download |
| 2 | Record of Conversation Pilot's Wife | PDF, 1 page | View Download |
| 3 | FAA Record of Conversation with Pilot | PDF, 2 pages | View Download |
| 4 | FAA Inspector Examination Notes | PDF, 11 pages | View Download |
| 5 | Maintenance Logbook Excerpts | PDF, 7 pages | View Download |
| 6 | N512RT Weight and Balance Calculation | PDF, 1 page | View Download |
| 7 | Photo Array | PDF, 2 pages | 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.