Accident Brantly B-2 N5955X,
ASN logo
ASN Wikibase Occurrence # 211111
 
This information is added by users of ASN. Neither ASN nor the Flight Safety Foundation are responsible for the completeness or correctness of this information. If you feel this information is incomplete or incorrect, you can submit corrected information.

Date:Sunday 25 June 2017
Time:12:15
Type:Silhouette image of generic BRB2 model; specific model in this crash may look slightly different    
Brantly B-2
Owner/operator:Private
Registration: N5955X
MSN: 96
Year of manufacture:1961
Total airframe hrs:837 hours
Engine model:Lycoming IVO-360-A1A
Fatalities:Fatalities: 0 / Occupants: 2
Aircraft damage: Substantial
Category:Accident
Location:St. Michael, AK -   United States of America
Phase: Standing
Nature:Survey
Departure airport:St. Michael Airport, AK (SMK/PAMK)
Destination airport:St. Michael Airport, AK (SMK/PAMK)
Investigating agency: NTSB
Confidence Rating: Accident investigation report completed and information captured
Narrative:
The pilot reported that, while in a high-hover profile conducting aerial reindeer herding operations, he decided to make a precautionary landing with the skid-equipped helicopter on “knee-high” tussocks in remote tundra due to several “left yaw movements” followed by an “uncommanded left yaw.” The pilot initiated a hovering autorotation from about 15 ft above ground level. During the landing sequence, the left skid assembly was damaged, and the helicopter settled forward and to the left, which resulted in the three main rotor blades impacting the tundra. All three main rotor blades separated midspan due to the impact, and the helicopter sustained substantial damage to the main rotor system and fuselage.
After the accident, the pilot spoke with a witness who heard the engine producing “popping” noises and then “quit.” At the time of the accident, the pilot reported he did not realize that the engine had lost power.
Postaccident examination of the airframe and engine by the pilot revealed no preimpact mechanical malfunctions that would have precluded normal operation. While inspecting the fuel cell, the pilot found 1/8 of a cup of water with about 5 gallons of fuel remaining.
During the aerial herding operations, the helicopter was shut down for refueling several times throughout the day, and no hot refueling operations were conducted. The pilot spoke with some local community members who were assisting him on the day of the aerial herding operations. The pilot found that, when the helicopter was last refueled before the accident flight and when the fuel was transferred from a steel drum with a pump system to a plastic jug for pouring in the helicopter, a water separating filter/funnel was not used by one of the local community members who was assisting the pilot with the refueling operations. The individual misunderstood the refueling operations and thought that the fuel filtering process would take place as the fuel was poured directly into the helicopter. Water was subsequently found in the steel drum that was used. The pilot reported that he conducted a preflight check of the helicopter’s fuel cell (sump) before the accident flight, and no fuel discrepancies were observed at the time.
The Federal Aviation Administration published Advisory Circular 20-125, “Water in Aviation Fuels,” which discussed the potential hazards of water in aviation fuels and stated, in part:
The pilot in command has the final responsibility to determine that the aircraft is properly serviced. The pilot in command should also be present during the refueling operation to inspect a sample of the fuel from the dispensing unit prior to fueling the aircraft.
Refueling from drum storage or cans should be considered as an unsatisfactory operation and one to be avoided whenever possible. All containers of this type should be regarded with suspicion and the contents carefully inspected, identified, and checked for water and other contamination.


Probable Cause: The pilot’s inadequate supervision of the refueling process, which resulted in a loss of engine power due to water contamination in the helicopter’s fuel system from the fuel drum and subsequent impact with terrain.


Accident investigation:
cover
  
Investigating agency: NTSB
Report number: ANC17CA044
Status: Investigation completed
Duration:
Download report: Final report

Sources:

NTSB

History of this aircraft

Other occurrences involving this aircraft
16 April 1983 N5955X Private 0 Rogue River, OR sub

Location

Revision history:

Date/timeContributorUpdates
16-May-2018 15:37 ASN Update Bot Added
03-Dec-2023 03:25 Ron Averes Updated [Aircraft type, Departure airport, Destination airport, Narrative]

Corrections or additions? ... Edit this accident description

The Aviation Safety Network is an exclusive service provided by:
Quick Links:

CONNECT WITH US: FSF on social media FSF Facebook FSF Twitter FSF Youtube FSF LinkedIn FSF Instagram

©2024 Flight Safety Foundation

1920 Ballenger Av, 4th Fl.
Alexandria, Virginia 22314
www.FlightSafety.org