R44 fatal accident - tail boom failure?
Rather strange and tragic report on the NTSB site, abbreviated here:
"On May 1, 2006, about 1430 Pacific daylight time, a Robinson R44 Raven II, Canadian registration C-FICL, impacted desert terrain near Desert Center, California. The Canadian certificated commercial pilot and the passenger were fatally injured; the helicopter was destroyed. The cross-country ferry flight departed Zamperini Field Airport (TOA), Torrance, California, at 1305
The accident pilot had taken delivery of the new helicopter from the Robinson Helicopter Company factory in Torrance on the day of the accident. The pilot and passenger, who were employed by Zimmer Air Service, Inc., departed from Torrance with an intended final destination of Blenheim, Ontario, Canada.
Two ground witnesses saw the helicopter just before it impacted the ground. They observed that the tail boom had separated from the fuselage.
The helicopter was a Robinson R44 Raven II, and had a total airframe time of 4.0 hours when it left the factory the day of the accident. The tachometer read 5.2 hours at the accident scene.
The on-scene examination revealed that the helicopter and separated components came to rest about 200 yards south of interstate 10. The accident site was 16 nm east of Desert Center, and 18 nm west of Blythe.
The tail boom was located 100 feet west of the main wreckage. The tail boom had separated just aft of the main fuselage attach point. The tail rotor blades and tail rotor transmission were attached to the tail boom with minor impact damage."
Where the tail boom separated doesn't sound quite like a failure following mast bumping/MR blade hitting tail boom scenario, but it is hard to think of any other cause. Any views/knowledge?