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 　　WASHINGTON, July 10 (Xinhua) -- U.S. Navy's X-47B Unmanned Combat Air System (UCAS) drone on Wednesday completed its first-ever carrier-based arrested landing on board USS George H.W. Bush off the coast of Virginia, the Navy announced.

　　"By evolving and integrating new technology like the X-47B and the unmanned aircraft to follow, carriers will remain relevant throughout their 50-year lifespan," said Secretary of the Navy Ray Mabus, according to a Navy statement.

　　The demonstration¹ was the first time a tailless, unmanned autonomous² aircraft landed on a modern aircraft carrier, the Navy said. Navy leaders believe the success will impact the way the Navy integrates manned and unmanned aircraft on the carrier flight deck in the future.

　　In May, X-47B successfully completed underway carrier deck operations aboard USS George H. W. Bush to include a first-ever catapult launch and nine touch-and-gos, a landing maneuver³ that involves landing on a runway and taking off again without coming to a full stop.

1 demonstration   

n.表明，示范，论证，示威

参考例句：

• His new book is a demonstration of his patriotism.他写的新书是他的爱国精神的证明。
• He gave a demonstration of the new technique then and there.他当场表演了这种新的操作方法。

2 autonomous   

adj.自治的；独立的

参考例句：

• They proudly declared themselves part of a new autonomous province.他们自豪地宣布成为新自治省的一部分。
• This is a matter that comes within the jurisdiction of the autonomous region.这件事是属于自治区权限以内的事务。

3 maneuver   

n.策略[pl.]演习；v.(巧妙)控制；用策略

参考例句：

• All the fighters landed safely on the airport after the military maneuver.在军事演习后，所有战斗机都安全降落在机场上。
• I did get her attention with this maneuver.我用这个策略确实引起了她的注意。