19991016029129A

(.19) On October 16, 1999, at 1410 hours pacific daylight time, a Sikorsky CH-54A, N9125M, was shutting down at Elko, Nevada, when a crewmember was struck by a rotor blade. The aircraft was not damaged nor was the airline transport-rated pilot or his copilot injured; however, the crew chief received fatal injuries. The aircraft was being operated as a positioning flight by siller brothers, inc., under 14 CFR part 91 when the accident occurred. The flight originated in tooele, Utah, at 1230 on the afternoon of the accident. Visual meteorological conditions prevailed at the time and a company flight plan was filed. According to the blm state aviation manager for the state of Nevada, while the aircraft was shutting down, the crew chief climbed up on a stepladder and was struck by a rotor blade. The aircraft was on a repositioning flight to its home station in yuba city, California, after being released from a call-when-needed exclusive use contract with the U.S. Forest service earlier that day. The stop in Elko was for fuel. (-23) on October 16, 1999, at 1410 hours PDT, a Sikorsky CH-54-A, N9125M enroute from tooele, Utah to yuba city, CA. Had landed at Elko, Nevada to refuel. The engines had been shut down and the rotor blades were winding down, when a crewmember (mechanic) was struck by a rotor blade. The a/c was not damaged nor was either pilot; however, the mechanic received fatal injuries. The a/c was being operated under 14 CFR part 91 (positioning flight) when the accident occurred. Visual meteorological conditions prevailed at the time and a company flight plan had been filed. According to the Nevada blm state aviation manager, while the helicopter rotor blades were winding down, the mechanic climbed onto the top of the helicopter and was struck by the rotor blades. (.4) on October 16, 1999, at 1410 hours pacific daylight time, a Sikorsky CH-54A, N9125M, was shutting down at Elko, Nevada, when a crewmember was struck by a rotor blade. The aircraft was not damaged nor was the airline transport-rated pilot or his copilot injured; however, the crew chief received fatal injuries. The aircraft was being operated as a positioning flight by siller brothers, inc., under 14 CFR part 91 when the accident occurred. The flight originated in tooele, Utah, at 1230 on the afternoon of the accident. Visual meteorological conditions prevailed at the time and a company flight plan was filed. According to the blm state aviation manager for the state of Nevada, while the aircraft was shutting down, the crew chief climbed up on a stepladder and was struck by a rotor blade. The aircraft was on a repositioning flight to its home station in yuba city, California, after being released from a call-when-needed exclusive use contract with the U.S. Forest service earlier that day. The stop in Elko was for fuel. According to the bureau of land management (blm) state aviation manager for the state of Nevada, while the a/c was being shutdown the flight engineer exited the a/c. he then gave the pilots the signal that the droop stops had engaged, and then climbed up on a stepladder next to the tail boom. A minute or so later, the two remaining crewmembers heard a "thump". The pilot in command (PIC) asked the copilot to go outside and find the source of the noise. When he walked toward the rear of the a/c, he found the flight engineer lying across the top of tail boom with a massive head injury. He returned to the cockpit and informed the PIC that the flight engineer was injured. The PIC called the tower, requesting immediate emergency medical aid. Emergency medical personnel who responded concluded that the flight engineer had been struck in the back of the head by a main rotor blade. The main rotor head of the CH-54A is fully articulated with each blade being free to flap independently of the remaining blades. The rotor system employs a series of mainrotor blade droop stops. As the rotor RPM slows, centripetal force is reduced and the droop stop spring pulls the stops back into ground stop position. Manufacturer's representative stated that during spool down it can take 20 seconds or more for the first through sixth stop to move into the ground stop position. The visual strobe effect, caused by the turning rotor head, can make it appear that all the stops are in place when one or more stops still have not been fully repositioned. A postaccident inspection of the static main rotor found all six droop stops fully in the ground stop position. Winds were gusting up to 14 knots at the time of the shutdown. No autopsy was performed. A toxicological studey was conducted on samples from the flight engineer by the washoe county sheriff's forensic science division. The results were negative for alcohol and all screened drug substances.