Thursday, February 14, 2019

Loss of Engine Power (total): Hughes 369E, N765KV, accident occurred June 23, 2017 in Dennis, West Virginia

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

Additional Participating Entities:

Federal Aviation Administration / Flight Standards District Office; Charleston, West Virginia
MD Helicopters; Phoenix, Arizona
Rolls-Royce; Indianapolis, Indiana
Boeing; Seattle, Washington
Haverfield Helicopters; Gettysburg, Pennsylvania

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/N765KV

Location: Dennis, WV
Accident Number: ERA17LA209
Date & Time: 06/23/2017, 1315 EDT
Registration: N765KV
Aircraft: HUGHES 369
Aircraft Damage: Substantial
Defining Event: Loss of engine power (total)
Injuries: 1 None
Flight Conducted Under: Part 133: Rotorcraft Ext. Load 

Analysis 

The commercial pilot was conducting long line operations in the helicopter, and he was flying it in an aft or left attitude with a higher nose-up attitude than normal flight to compensate for the load's drag. He then transitioned the helicopter to a 100-ft hover over a landing zone, and shortly thereafter, the helicopter experienced a total loss of engine power. Subsequently, the pilot initiated an autorotation, and during the landing, a main rotor blade contacted and severed the tailboom.

Postaccident wreckage examination, which included a successful test-run of the engine, did not reveal evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. However, when the helicopter was positioned nose up with the remaining fuel onboard (about 7 gallons in each tank), the low fuel light illuminated. The two fuel tanks were connected by an interconnect passage, and each tank had an internal baffle. The fuel pickup was located in the right front portion of the left fuel tank. Given that the low fuel light illuminated when the helicopter was positioned nose up, it is likely that the helicopter's nose-up attitude during the long line operation led to the unporting of the remaining fuel, which resulted in fuel starvation.

The operator's risk assessment form required that pilots land the helicopter with at least about 14.7 gallons of fuel remaining for long line operations. After the accident, the operator amended its risk assessment form to require the same fuel requirement as side pull operations (about 37 gallons of fuel remaining upon landing) for long line operations.

Probable Cause and Findings

The National Transportation Safety Board determines the probable cause(s) of this accident to be: 
The unporting of fuel due to the helicopter's nose-up attitude during long line operations, which resulted in fuel starvation and a total loss of engine power.

Findings

Aircraft
Fuel system - Not specified (Cause)

Factual Information 

History of Flight

Maneuvering
Fuel starvation

Maneuvering-hover
Loss of engine power (total) (Defining event)

Autorotation
Hard landing

Landing

Part(s) separation from AC

On June 23, 2017, about 1315 eastern daylight time, a Hughes 369E, N765KV, operated by Haverfield Aviation Inc, was substantially damaged during a hard landing near Dennis, West Virginia. The commercial pilot was not injured. The external load flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 133. Visual meteorological conditions prevailed and no flight plan was filed for the local flight.

The pilot reported that he returned to the landing zone with a conductor attached to a long line. The helicopter was in a 100-foot hover over the landing zone, while the pilot monitored a ground crewmember tasked to disconnect the conductor from the long line. The helicopter began to settle and the pilot raised the collective control; however, the helicopter continued to settle as a warning horn sounded and the engine noise ceased. The pilot then entered an autorotation and during the landing, a main rotor blade contacted the tailboom, which resulted in a tailboom separation.

The pilot added that prior to the hover, he was pulling the conductor with the helicopter in an aft or left attitude. He estimated that the loss of engine power occurred 45 seconds to 1 minute after transitioning from the pull to a hover.

A Federal Aviation Administration (FAA) inspector witnessed a subsequent wreckage examination, which included a successful test-run of the engine. No preimpact mechanical malfunctions were noted and the low fuel light illuminated when the helicopter was positioned nose-up with the remaining fuel onboard. The inspector added that approximately 7 gallons of fuel remained in each of the two fuel tanks at the time of the loss of engine power. The two fuel tanks were connected by an interconnect passage and each tank had an internal baffle. The fuel pickup was located in the right front portion of the left fuel tank.

The FAA inspector further stated that during the accident flight, the conductor was not completely off the ground and was being dragged over terrain. To compensate for the dragging resistance, the pilot had the helicopter in an aft or left attitude, with a higher nose-up attitude than normal flight. The operator's risk assessment form required that the helicopter be topped off (64 gallons) with fuel prior to and only fly for 1 hour during side pull operations, which would leave about 37 gallons of fuel remaining. For all other operations, including long line operations, the fuel requirement was to land with at least 100 lbs. (about 14.7 gallons) of fuel remaining. At the time of the accident, the helicopter had about 14 gallons of fuel remaining. After the accident, the operator amended its risk assessment form to include the same fuel requirement in long line operations as side pull operations. 

Pilot Information

Certificate: Commercial
Age: 31, Male
Airplane Rating(s): None
Seat Occupied: Left
Other Aircraft Rating(s): Helicopter
Restraint Used: 4-point
Instrument Rating(s): Helicopter
Second Pilot Present: No
Instructor Rating(s): Helicopter; Instrument Helicopter
Toxicology Performed: No
Medical Certification: Class 1 Without Waivers/Limitations
Last FAA Medical Exam: 06/02/2017
Occupational Pilot: Yes
Last Flight Review or Equivalent: 04/30/2016
Flight Time:   4325 hours (Total, all aircraft), 2556 hours (Total, this make and model), 4282 hours (Pilot In Command, all aircraft), 126 hours (Last 90 days, all aircraft), 43 hours (Last 30 days, all aircraft), 0 hours (Last 24 hours, all aircraft)

Aircraft and Owner/Operator Information

Aircraft Make: HUGHES
Registration: N765KV
Model/Series: 369 E
Aircraft Category: Helicopter
Year of Manufacture: 1980
Amateur Built: No
Airworthiness Certificate: Normal
Serial Number: 0082E
Landing Gear Type: Skid
Seats: 4
Date/Type of Last Inspection: 06/06/2017, 100 Hour
Certified Max Gross Wt.: 3000 lbs
Time Since Last Inspection: 16 Hours
Engines: 1 Turbo Shaft
Airframe Total Time: 28285 Hours at time of accident
Engine Manufacturer: Rolls-Royce
ELT: C126 installed, activated, did not aid in locating accident
Engine Model/Series: 250 C20B
Registered Owner: HAVERFIELD INTERNATIONAL INC
Rated Power: 420 hp
Operator: HAVERFIELD INTERNATIONAL INC
Operating Certificate(s) Held: Rotorcraft External Load (133)
Operator Does Business As: HAVERFIELD AVIATION INC
Operator Designator Code: 

Meteorological Information and Flight Plan

Conditions at Accident Site: Visual Conditions
Condition of Light: Day
Observation Facility, Elevation: LWB, 2301 ft msl
Distance from Accident Site: 15 Nautical Miles
Observation Time: 1315 EDT
Direction from Accident Site: 120°
Lowest Cloud Condition:
Visibility:  7 Miles
Lowest Ceiling: Broken / 3200 ft agl
Visibility (RVR):
Wind Speed/Gusts: 8 knots /
Turbulence Type Forecast/Actual: / None
Wind Direction: 240°
Turbulence Severity Forecast/Actual: / N/A
Altimeter Setting: 29.97 inches Hg
Temperature/Dew Point: 22°C / 19°C
Precipitation and Obscuration: Light - Rain; No Obscuration
Departure Point: Dennis, WV
Type of Flight Plan Filed: None
Destination: Dennis, WV
Type of Clearance: None
Departure Time: 1215 EDT
Type of Airspace:

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: 38.038889, -80.730833 (est)

NTSB Identification: ERA17LA209
14 CFR Part 133: Rotorcraft Ext. Load
Accident occurred Friday, June 23, 2017 in Dennis, WV
Aircraft: HUGHES 369, registration: N765KV
Injuries: 1 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 23, 2017, about 1315 eastern daylight time, a Hughes 369E, N765KV, operated by Haverfield Aviation Inc, was substantially damaged during a hard landing near Dennis, West Virginia. The commercial pilot was not injured. The external load flight was conducted under the provisions of 14 Code of Federal Regulations Part 133. Visual meteorological conditions prevailed and no flight plan was filed for the local flight.

The pilot reported that he returned to the landing zone with a conductor attached to a long line. The helicopter was in a 100-foot hover over the landing zone, while the pilot monitored a ground crewmember disconnect the conductor from the long line. The helicopter began to settle and the pilot raised the collective control; however, the helicopter continued to settle as a warning horn sounded and the engine noise ceased. The pilot then entered an autorotation and during the landing, a main rotor blade contacted the tailboom, which resulted in a tailboom separation.

Further examination of the helicopter was planned following its recovery to the operator's facility.

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