National Transportation Safety Board
Aviation Accident Preliminary Report
Location: Elgin, MN Accident Number: CEN21FA330
Date & Time: July 19, 2021, 15:30 Local Registration: N44BJ
Aircraft: Robinson R44 Injuries: 1 Fatal
Flight Conducted
Part 137: Agricultural
Under:
On July 19, 2021, about 1530 central daylight time, a Robinson R44 II helicopter, N44BJ, was destroyed
when it was involved in an accident near Elgin, Minnesota. The pilot was fatally injured. The airplane
was operated as a Title 14 Code of Federal Regulations Part 137 aerial-application flight.
A witness observed the helicopter flying east-and-west aerial-application passes over a corn field, with
each additional pass progressing closer toward the north end of the field being sprayed. The witness
observed the helicopter fly over the power lines that crossed the corn field during two consecutive
passes, but on the third pass the helicopter flew under the power lines while heading westbound. The
witness had entered a nearby pole barn when he heard a loud boom, and the pole barn shook
momentarily. He then exited the pole barn and saw smoke rising from where the helicopter had crashed
in the corn field. The witness and his father then responded to the accident site where they observed the
helicopter engulfed in flames.
The initial impact was with a three-phase power transmission line. The western line remained intact, the
center line exhibited fraying, and the eastern line was severed (Photo 1 and 2). The power lines
consisted of three (477ACSR type) 24 aluminum conducting strands over 7 steel strands. The GPS
altitude at the surface below the power lines was 1,080 ft. The frayed power line at the point of damage
was about 28 ft above the ground. The corn crop under the power lines was 8-10 ft tall. Portions of the
swashplate yoke, a blade droop tusk, pilot’s headset, sunglasses and ballcap, and plexiglass fragments
were located under and immediately east of the power lines.
Page 1 of 6 CEN21FA330
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when
the final report has been completed.
Photo 1 – Power Lines (red circle identifies the center power line that was frayed)
Page 2 of 6 CEN21FA330
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when
the final report has been completed.
Photo 2 – View Back Toward Power Lines (Red Circle is Frayed Center Power Line)
The wreckage debris path measured 292 ft between the power lines and the main wreckage. The
wreckage debris path through the corn crop was on a 90° heading. The helicopter impacted terrain in a
15° descent angle, as evidenced by the damaged corn crop. Fractured portions of the spray booms, cabin
door, and plexiglass were scattered along the wreckage debris path.
The main wreckage included remnants of the cabin, landing skids, cockpit, engine, main rotor
transmission, main rotor head, main rotor blades, aft fuselage, sheaves, tail rotor drive shaft, tail boom,
tail rotor gear box, and tail rotor blades (Photo 3). The relatively intact product tank and its support
frame was located about 15 ft north of the main wreckage. Most of the cabin and cockpit were destroyed
by the postimpact fire. Flight control continuity could not be established due to extensive damage
sustained during impact and postimpact fire. The postaccident examination did not reveal any evidence
of a mechanical malfunction of the helicopter or its engine that would have precluded normal flight.
Page 3 of 6 CEN21FA330
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when
the final report has been completed.
Photo 3 – Main Wreckage
The outboard 3 ft of one main rotor blade was not located during the investigation. The blade fracture
exhibited damage consistent with impact with a power line (Photo 4). The other main rotor blade
remained intact but folded in half.
Page 4 of 6 CEN21FA330
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when
the final report has been completed.
Photo 4 – Fractured Main Rotor Blade with Severed Power Line
The height of the corn under the power lines measured 8-10 ft. The operator stated that the helicopter is
typically flown 10 ft above the crop to ensure optimal spray disbursement. According to the Robinson
R44 II Pilot Operating Handbook (POH), the helicopter was 10.75 ft tall. The frayed power line at the
point of damage was about 28 ft above the ground.
Aircraft and Owner/Operator Information
Aircraft Make: Robinson Registration: N44BJ
Model/Series: R44 II Aircraft Category: Helicopter
Amateur Built: No
Operator: Operating Certificate(s) Agricultural aircraft (137)
Held:
Operator Designator Code:
Page 5 of 6 CEN21FA330
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when
the final report has been completed.
Meteorological Information and Flight Plan
Conditions at Accident Site: VMC Condition of Light: Day
Observation Facility, Elevation: RST,1304 ft msl Observation Time: 15:54 Local
Distance from Accident Site: 17 Nautical Miles Temperature/Dew Point: 28°C /17°C
Lowest Cloud Condition: Few / 4800 ft AGL Wind Speed/Gusts, Direction: 5 knots / , 280°
Lowest Ceiling: Visibility: 10 miles
Altimeter Setting: 30.2 inches Hg Type of Flight Plan Filed: None
Departure Point: Elgin, MN Destination: Elgin, MN
Wreckage and Impact Information
Crew Injuries: 1 Fatal Aircraft Damage: Destroyed
Passenger Injuries: Aircraft Fire: On-ground
Ground Injuries: Aircraft Explosion: Unknown
Total Injuries: 1 Fatal Latitude, 44.108056,-92.204167
Longitude:
Administrative Information
Investigator In Charge (IIC): Fox, Andrew
Additional Participating Persons: Nikolas Halatsis; Federal Aviation Administration - Minneapolis FSDO; Minneapolis, MN
Troy Helgeson; Lycoming Engines; Milliken, CO
Note:
Page 6 of 6 CEN21FA330
This is preliminary information, subject to change, and may contain errors. Any errors in this report will be corrected when
the final report has been completed.
