Additional Participating Entity:
Federal Aviation Administration / Flight Standards District Office; Indianapolis, Indiana
Aviation Accident Final Report - National Transportation Safety Board:
https://app.ntsb.gov/pdf
Investigation Docket - National Transportation Safety Board:
https://dms.ntsb.gov/pubdms
Aviation Accident Data Summary - National Transportation Safety Board: https://app.ntsb.gov/pdf
http://registry.faa.gov/N3203D
Location: Paoli, IN
Accident Number: GAA17CA401
Date & Time: 07/07/2017, 1600 CDT
Registration: N3203D
Aircraft: ROBINSON HELICOPTER COMPANY R44
Aircraft Damage: Substantial
Defining Event: Low altitude operation/event
Injuries: 1 None
Flight Conducted Under: Part 137: Agricultural
Analysis
The helicopter pilot reported that he was performing an agricultural application flight and was in a hurry to spray the field because of a previous 3-hour delay caused by a broken fuel truck. The pilot reported that the weight of the helicopter was 60 lbs above the helicopter's maximum gross weight and that he "approached the field with the understanding that I was heavier, and it was hotter and more windy than I originally planned for."
The pilot reported that the helicopter was headed south and that the wind was from the southwest about 15 knots. He made a low-altitude, low-airspeed, left turn to the north, and the helicopter entered a nose-low attitude and sank more rapidly than he anticipated. The pilot aborted the turn and chose to maintain a southeast heading to use the crosswind to avoid power lines. He attempted to arrest the sink rate by increasing the collective, but the low rotor rpm horn sounded.
The helicopter impacted the ground, bounced, and then rolled onto its left side. The helicopter sustained substantial damage to the tailboom and the main rotor system.
The nearest METAR was about 32 miles northwest of the accident site, and it reported, at the time of the accident, wind from 230° at 9 knots, gusting to 16 knots. The temperature was 88°F and the dew point was 20°F. The field elevation was 696 ft, and the density altitude was 2,786 ft.
According to the Federal Aviation Administration (FAA) Helicopter Flying Handbook, FAA-8083-21A (pg. 2-4, para. 5), "turns in a helicopter increase the load factor exponentially, ultimately increasing the power requirement that is necessary to maintain the helicopter's altitude. Left pedal turns increase the quantity of anti-torque produced by the tail rotor, by demanding additional power from the 260-brake horsepower engine. Pilot flight control inputs demanding more power than the engine is capable of producing, with respect to the atmospheric conditions, adversely affects the helicopter's ability to sustain its altitude. Available engine power is directly correlated to main and tail rotor RPM. When the engine fails to produce the required power to sustain airspeed and altitude at high DA [descent altitude], the main rotor blades will exceed their critical angle of attack, consequently decreasing main rotor blade RPM."
The pilot reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.
Probable Cause and Findings
The National Transportation Safety Board determines the probable cause(s) of this accident to be:
The pilot's decision to maneuver an overgross weight helicopter at a low altitude and airspeed with a gusting tailwind, which resulted in a high descent rate and collision with terrain. Contributing to the accident was the pilot's self-induced pressure to complete the operations due to a delay before the operations began.
Findings
Aircraft
Climb rate - Not attained/maintained (Cause)
Maximum weight - Capability exceeded
Personnel issues
Decision making/judgment - Pilot (Cause)
Motivation/respond to pressure - Pilot (Factor)
Environmental issues
Tailwind - Effect on equipment
Location: Paoli, IN
Accident Number: GAA17CA401
Date & Time: 07/07/2017, 1600 CDT
Registration: N3203D
Aircraft: ROBINSON HELICOPTER COMPANY R44
Aircraft Damage: Substantial
Defining Event: Aerodynamic stall/spin
Injuries: 1 None
Flight Conducted Under: Part 137: Agricultural
The helicopter pilot reported that he was performing an agricultural flight and was in a hurry to spray the field because of a previous 3-hour delay caused by a broken fuel truck.
The pilot reported that the weight of the helicopter was sixty pounds above the helicopter's maximum gross weight, and "I approached the field with the understanding that I was heavier, and it was hotter and more windy than I originally planned for."
He reported that the helicopter was headed south, and the wind was from the southwest about 15 knots.
The pilot made a low altitude, low airspeed, left turn to the north, and the helicopter entered a nose low attitude and had a more rapid sink rate than he anticipated. The pilot aborted the turn and chose to maintain a southeast heading to utilize the crosswind to avoid powerline wires. He attempted to arrest the sink rate by increasing the collective, but the low rotor RPM horn sounded.
The helicopter impacted the ground and bounced, then it rolled onto its left side. The helicopter sustained substantial damage to the tailboom, and the main rotor system.
The nearest METAR was about 32 miles northwest at the time of the accident reported and the wind was from 230° at 9 knots gusting to 16 knots. The temperature was 88°F and the dew point was 20°F. The field elevation was 696 feet and the density altitude was 2,786 feet.
According to the Federal Aviation Administration (FAA) Helicopter Flying Handbook, FAA-8083-21A (pg. 2-4, para. 5), turns in a helicopter increase the load factor exponentially, ultimately increasing the power requirement that is necessary to maintain the helicopter's altitude. Left pedal turns increase the quantity of anti-torque produced by the tail rotor, by demanding additional power from the 260-brake horsepower engine. Pilot flight control inputs demanding more power than the engine is capable of producing, with respect to the atmospheric conditions, adversely affects the helicopters ability to sustain its altitude. Available engine power is directly correlated to main and tail rotor RPM. When the engine fails to produce the required power to sustain airspeed and altitude at high DA, the main rotor blades will exceed their critical angle of attack, consequently decreasing main rotor blade RPM.
According to the FAA Helicopter Instructor's Handbook, FAA-8083-4 (pg. 8-4, para. 5), If a pilot begins a landing approach with a 10 knot tailwind, at some time in the approach, the helicopter experiences a zero knot airspeed, which means a total loss of translational lift and thrust. In order to maintain the approach angle, more power must be added.
The pilot reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.
Pilot Information
Certificate: Flight Instructor; Commercial
Age: 28, Male
Airplane Rating(s): Single-engine Land
Seat Occupied: Right
Other Aircraft Rating(s): Helicopter
Restraint Used:
Instrument Rating(s): Helicopter
Second Pilot Present: No
Instructor Rating(s): Helicopter; Instrument Helicopter
Toxicology Performed: No
Medical Certification: Class 2 With Waivers/Limitations
Last FAA Medical Exam: 03/10/2017
Occupational Pilot: Yes
Last Flight Review or Equivalent: 03/17/2016
Flight Time: (Estimated) 1548 hours (Total, all aircraft), 797 hours (Total, this make and model), 1450 hours (Pilot In Command, all aircraft)
Aircraft and Owner/Operator Information
Aircraft Manufacturer: ROBINSON HELICOPTER COMPANY
Registration: N3203D
Model/Series: R44 II
Aircraft Category: Helicopter
Year of Manufacture: 2005
Amateur Built: No
Airworthiness Certificate: Restricted
Serial Number: 11598
Landing Gear Type: Skid;
Seats: 4
Date/Type of Last Inspection: 03/21/2017, 100 Hour
Certified Max Gross Wt.: 2400 lbs
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 1827 Hours
Engine Manufacturer: LYCOMING
ELT: Not installed
Engine Model/Series: IO-540-F1B5
Registered Owner: Jonathan Mabry
Rated Power: 205 hp
Operator: JMX Helicopters
Operating Certificate(s) Held: Agricultural Aircraft (137)
Meteorological Information and Flight Plan
Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KDCY, 470 ft msl
Observation Time: 1955 UTC
Distance from Accident Site: 32 Nautical Miles
Direction from Accident Site: 283°
Lowest Cloud Condition:
Temperature/Dew Point: 31°C / 20°C
Lowest Ceiling: Broken / 4500 ft agl
Visibility: 10 Miles
Wind Speed/Gusts, Direction: 9 knots/ 16 knots, 230°
Visibility (RVR):
Altimeter Setting: 29.89 inches Hg
Visibility (RVV):
Precipitation and Obscuration: No Obscuration; No Precipitation
Departure Point: Sparta, IL (SAR)
Type of Flight Plan Filed: None
Destination: Washington, IN
Type of Clearance: None
Departure Time: 0600 CDT
Type of Airspace: Class G
Wreckage and Impact Information
Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: N/A
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 None
Latitude, Longitude: 38.585556, -86.464722 (est)
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