增加一个桨叶(主桨有5个叶片，尾桨有4个)，并使用了改进的排气系统。

Adding a rotor blade (it had five on the main rotor and four on the tail) and using a modified exhaust system were among them.

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中至尾排气喉，R77D新款双咀碳纤维设计。

R77D 3/4 slip-on exhaust system. New design double exit.

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中至尾排气喉，R77D新款双咀碳纤维设计。

R77D 3/4 slip-on exhaust system. New design double exit.

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