It is a good practice to check the bolts and nuts on the main rotor head and tail rotor after every flight.

每次飞完检查主旋翼头和尾旋翼头的螺丝螺母是一个很好的习惯。

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It included the black box flight recorder, the fuselage with the engines and rotor gearbox attached, the separated rotor head with the main rotor blades still attached, and the separated tail.

BBC: Crash report urges safety checks