The prototype test of the maingearbox at the test bench shall be completed before issuance of the ADesign Assessment (see Section 10.7).
在试验台对主齿轮箱的样机试验应在A-设计评审签发前完成（见第10.7节）。
2
Through analyzing the problem of short life of gears in the maingearbox, the design programme for composite hard-surface gears in high-speed level is described.
通过对主减速机齿轮寿命不足问题的分析，提出了在高速级采用组合式硬齿面齿轮的设计方案。
3
It is powered by two jet-turbine engines which operate both the five-bladed main rotor and, through a gearbox and shafts, a pair of propellers on two short wings.