Saturday, June 10, 2017

Robinson R44 II , N590GG, registered to and operated by Wagonhound Land and Livestock Co LLC: Accident occurred June 09, 2017 in Douglas, Converse County, Wyoming

The National Transportation Safety Board did not travel to the scene of this accident.

Additional Participating Entity: Federal Aviation Administration / Flight Standards District Office; Casper, Wyoming

Aviation Accident Factual Report - National Transportation Safety Board:  https://app.ntsb.gov/pdf

http://registry.faa.gov/N590GG




Location: Douglas, WY
Accident Number: CEN17LA219
Date & Time: 06/09/2017, 0820 MDT
Registration: N590GG
Aircraft: ROBINSON HELICOPTER COMPANY R44 II
Aircraft Damage: Substantial
Defining Event: Settling with power/vortex ring state
Injuries: 1 Serious, 3 None
Flight Conducted Under:  Part 91: General Aviation - Business 

On June 9, 2017, about 0820 mountain daylight time, a Robinson R44 II helicopter, N590GG, impacted terrain near Douglas, Wyoming. The pilot and two passengers were not injured, the third passenger received serious injuries, and the helicopter was substantially damaged during the accident. The helicopter was registered to and operated by Wagonhound Land and Livestock Co, LLC, under the provisions of 14 Code of Federal Aviation Regulations Part 91. Visual meteorological conditions prevailed at the time.

The pilot reported that he topped the fuel off at the Converse County airport (KDGW); then he and one other person departed the airport with calm winds. They traveled about 25 miles to a lodge to pick up two additional passengers. The pilot shut the helicopter down, for the passengers to board; while there, he estimated there was a steady west wind at 12-15 knots. They then departed the lodge and did some sightseeing en route to a ranch/stockyard. The pilot reported that he climbed to 1,000 ft as they passed KDGW. The automated weather station located at the KGDW was reporting wind, variable at 3 knots.

As they approached the cattle stockyards, they looked at crop status, fields, building irrigation machinery, etc. During that time, the pilot looked at trees, pond surfaces, and ground track which indicated a calm wind condition. The pilot then selected an approach course for a landing, which would avoid a barn and work crews; aiming for clear sport near water tanks.

During the approach, the pilot noted that the power and glide path indications were normal, he noticed the last airspeed was at 30 kts and 100 ft agl. The pilot added that "somewhere below 50 ft agl" there was a sudden, abrupt, high rate of descent; he manipulated the controls and the helicopter's low rpm light illuminated and the warning horn sounded. He continued, saying there was no time or altitude to lower the collective and regain rpm. The helicopter impacted terrain and rolled to the side when the left skid failed. The pilot added that after the accident, the engine continued to run and there was no prior mechanical malfunction/failure with the helicopter. He noted there was a steady northwest wind estimated at 15 kts.

Based on the conditions at the time of the accident, the calculated density altitude was 7,015 ft, and the helicopter was near the maximum gross weight of 2,500 lbs.

Helicopter Flying Handbook, FAA-H-8083-21A,

Chapter 11, Helicopter Emergencies and Hazards

Settling with Power (Vortex Ring State)

Vortex ring state describes an aerodynamic condition in which a helicopter may be in a vertical descent with 20 percent up to maximum power applied, and little or no climb performance. The term "settling with power" comes from the fact that the helicopter keeps settling even though full

engine power is applied.

…. Tip vortices generate drag and degrade airfoil efficiency. As long as the tip vortices are small, their only effect is a small loss in rotor efficiency. However, when the helicopter begins to descend vertically, it settles into its own downwash, which greatly enlarges the tip vortices. In this vortex ring state, most of the power developed by the engine is wasted in circulating the air in a doughnut pattern around the rotor…..

….. A vortex ring state may be entered during any maneuver that places the main rotor in a condition of descending in a column of disturbed air and low forward airspeed. Airspeeds that are below translational lift airspeeds are within this region of susceptibility to settling with power aerodynamics….

… Some of the situations that are conducive to a settling with power condition are: any hover above ground effect altitude, specifically attempting to hover OGE [ out-of-ground-effect ]at altitudes above the hovering ceiling of the helicopter, attempting to hover OGE without maintaining precise altitude control, pinnacle or rooftop helipads when the wind is not aligned with the landing direction, and downwind and steep power approaches in which airspeed is permitted to drop below 10 knots depending on the type of helicopter. 

Pilot Information

Certificate: Airline Transport; Commercial
Age: 66
Airplane Rating(s): Multi-engine Land; Multi-engine Sea; Single-engine Land; Single-engine Sea
Seat Occupied: Right
Other Aircraft Rating(s): Gyroplane; Helicopter
Restraint Used:
Instrument Rating(s): Airplane; Helicopter
Second Pilot Present: No
Instructor Rating(s): Airplane Multi-engine; Airplane Single-engine; Gyroplane; Helicopter; Instrument Airplane; Instrument Helicopter
Toxicology Performed: No
Medical Certification: Class 2 With Waivers/Limitations
Last FAA Medical Exam: 12/05/2016
Occupational Pilot: Yes
Last Flight Review or Equivalent: 03/15/2017
Flight Time: 17457 hours (Total, all aircraft), 4848 hours (Total, this make and model) 

Aircraft and Owner/Operator Information

Aircraft Manufacturer: ROBINSON HELICOPTER COMPANY
Registration: N590GG
Model/Series: R44 II II
Aircraft Category: Helicopter
Year of Manufacture:2016
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 13973
Landing Gear Type: Ski;
Seats:
Date/Type of Last Inspection: 02/24/2017, Annual
Certified Max Gross Wt.:
Time Since Last Inspection:
Engines: 1 Reciprocating
Airframe Total Time: 112.9 Hours at time of accident
Engine Manufacturer: LYCOMING
ELT: Not installed
Engine Model/Series: IO-540-AE1A5
Registered Owner: On file
Rated Power: 245 hp
Operator: On file
Operating Certificate(s) Held: None

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: KDGW
Observation Time: 0853
Distance from Accident Site: 
Direction from Accident Site:
Lowest Cloud Condition: Clear
Temperature/Dew Point: 22°C / 1°C
Lowest Ceiling: None
Visibility:  10 Miles
Wind Speed/Gusts, Direction: 13 knots/ 19 knots, 240°
Visibility (RVR):
Altimeter Setting: 29.81 inches Hg
Visibility (RVV):
Precipitation and Obscuration:
Departure Point: Douglas, WY
Type of Flight Plan Filed: None
Destination: Douglas, WY
Type of Clearance: None
Departure Time:
Type of Airspace: 

Wreckage and Impact Information

Crew Injuries: 1 None
Aircraft Damage: Substantial
Passenger Injuries: 1 Serious, 2 None
Aircraft Fire: None
Ground Injuries: N/A
Aircraft Explosion: None
Total Injuries: 1 Serious, 3 None

Latitude, Longitude:  42.836667, -105.409722 (est)

NTSB Identification: CEN17LA219
14 CFR Part 91: General Aviation
Accident occurred Friday, June 09, 2017 in Douglas, WY
Aircraft: ROBINSON HELICOPTER COMPANY R44 II, registration: N590GG
Injuries: 1 Serious, 3 Uninjured.

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. NTSB investigators may not have traveled in support of this investigation and used data provided by various sources to prepare this aircraft accident report.

On June 9, 2017, about 0820 mountain daylight time, a Robinson R44 helicopter, N590GG, impacted terrain near Douglas, Wyoming. The pilot and two passengers were not injured, the third passenger received serious injuries. The helicopter was substantially damaged during the accident. The helicopter was registered to and operated by Wagonhound Land and Livestock Co, LLC, under the provisions of 14 Code of Federal Aviation Regulations Part 91. Visual meteorological conditions prevailed at the time. 

The pilot reported to the responding Federal Aviation Administration (FAA) inspector, that he was approaching cattle stockyards for a landing. He added that he was conducting a steep approach to avoid the disturbing the cattle, when the helicopter got hit with a tailwind. The helicopter then dropped, impacting terrain, before rolling over on its side. 

The wreckage was relocated to a secure facility for further examination.
=======

A helicopter crash northwest of Douglas on Friday morning resulted in minor injuries, Converse County Sheriff Clint Becker said.

A couple of people were taken to the Converse County Memorial Hospital for treatment, Becker said.

A helicopter belonging to the Wagonhound Land & Livestock Co. was about to land at one of its ranches when the crash occurred near Wyoming Highway 93 about five-and-a-half miles north of Douglas, Becker said. The wind was blowing hard at the time, he added.

The Sheriff's Office, Converse County Volunteer Fire Department and an ambulance service responded to the scene, he said.

The helicopter appeared to sustain damage to the rotors, Becker said. He did not know the make or model of the helicopter.

The National Transportation Safety Board is on the way to investigate the crash, he said.

Original article can be found here:  http://k2radio.com

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