Robinson R44 accident near Last Chance, Colorado, June 8, 2019
On June 8, 2019 at about 5:59 pm local time, a 2011 Robinson R44 (helicopter), registered N4504L, was substantially damaged in an accident during maneuvering (low-alt flying) near Last Chance, Colorado. 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 maintain adequate main rotor rpm while descending with a tailwind during an aerial application maneuver, which resulted in an uncontrolled descent into terrain.
Source: NTSB aviation accident database, copy made October 5, 2026. Docket and reports at the NTSB.
What the record shows
- Date
- June 8, 2019 · about 5:59 pm local time
- Place
- Last Chance, Colorado · map
- Type
- Accident
- Injuries
- 1 person had minor injuries.
- Weather
- visual conditions (good weather)
- Aircraft
- Robinson R44 II, built 2011 · all R44s on the register
- Registration
- N4504L · no longer on the register · serial 13084
- 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 helicopter pilot was performing an agricultural application flight. He approached the field from the east and completed a survey of the area that he intended to spray about 100 ft above ground level (agl). After maneuvering around the area, he decided to complete the east-west spray passes on the south side of the field and work north in order to have a crosswind during the passes. While flying east about 100 ft and 50 knots, he initiated a right turn, and the helicopter descended. As the helicopter continued the right turn and passed through a southwest heading, the gusting wind from the northeast resulted in a tailwind condition. During the descent with full throttle applied, the main rotor rpm began to decrease. The pilot lowered the collective and pitched forward to gain airspeed, but the main rotor rpm continued to decrease. About 50 ft agl, he started to jettison the spray load and was unable to increase the rotor rpm; the helicopter subsequently impacted the ground and came to rest on its side resulting in substantial damage to the tailboom. A postaccident examination of the helicopter did not reveal any anomalies that would have precluded normal operation. The circumstances of the accident are consistent with a loss of main rotor rpm while descending with a tailwind, which resulted in an uncontrolled descent into terrain.
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
- Loss of lift during maneuvering (low-alt flying) defining event
The NTSB's findings
- cause Personnel issues › Task performance › Use of equip/info › Aircraft control › Pilot
- cause Aircraft › Aircraft oper/perf/capability › Performance/control parameters › Descent rate › Not attained/maintained
- Environmental issues › Conditions/weather/phenomena › Wind › Tailwind › Decision related to condition
- Environmental issues › Conditions/weather/phenomena › Wind › Tailwind › Effect on equipment
- Environmental issues › Conditions/weather/phenomena › Wind › Tailwind › Response/compensation
- Environmental issues › Conditions/weather/phenomena › Wind › Tailwind › Awareness of condition
- Environmental issues › Conditions/weather/phenomena › Wind › Tailwind › Contributed to outcome
Pilot
- Certificate: flight instructor, commercial pilot
- Ratings: single-engine land; instructor: helicopter; instrument: airplane; instrument: helicopter; rotorcraft: helicopter
- Flight time: 1,539 hours in all; 1,261 in this make and model; 50 in the last 90 days; 42 in the last 30 days; 1,416 as pilot in command; 2 on instruments
- Last flight review: June 3, 2017
- Medical certificate: Class 2 (without waivers/limitations)
- Seat: rgt
- Injury: minor injuries
The aircraft
- Airframe total time: 1,809.8 hours
- Last inspection: 100-hour inspection, January 24, 2019
- Maximum gross weight: 2,500 lb
- Seats: 4
- Landing gear: fixed
- Engine: Lycoming IO-540-AE1A5 (piston); 1,810 hours total
The flight
- Departed from: Last Chance CO at 5:20 pm
- Destination: Last Chance CO
- Flight plan: none
Weather at the time
- Light: daylight
- Wind: from 021° at 17 knots, gusting 21
- Sky: clear
- Temperature: 73°F (23°C), dew point 50°F (10°C)
- Altimeter: 29.94 inHg
- Observation at 5:34 pm, 3 miles away
Injuries
| Fatal | Serious | Minor | None | |
|---|---|---|---|---|
| Flight crew | 1 |
Documents from the investigation the NTSB's docket: the evidence folder behind the report
8 documents, released by the NTSB on November 19, 2020. 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, 9 pages | View Download |
| 2 | Correspondence - Owner | PDF, 1 page | View Download |
| 3 | Correspondence - Pilot | PDF, 1 page | View Download |
| 4 | Correspondence - FAA Inspector | PDF, 1 page | View Download |
| 5 | Photos | PDF, 7 pages | View Download |
| 6 | Flight Track Tabular Data | data file | Download |
| 7 | Release of Aircraft Wreckage, NTSB Form 6120.15 | PDF, 1 page | View Download |
| 8 | Weather Reports and Records | 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.