Deliveries of operational aircraft were to begin in 2010 .

作战飞机的交付将在2010年开始。

A new system measures troops in terms of operational effectiveness .

新体系根据作战效能来衡量军力。

Along with a loss of revenue , cancellations cause operational chaos .

随着收入损失，取消订单导致了操作上的问题。

The bomber appears to have been invited to an operational planning meeting on al qaeda , a former senior u. s.intelligence official said .

一名前美国高级情报官员说，袭击者看来是受邀参加一个有关基地组织的作战计划会议。

U. s. officials say they believe china 's new generation stealth fighter , the j-20 , will be operational as early as 2018 .

美国官员说，他们认为中国新一代隐形战机歼-20最早将在2018年具备作战能力。