Helicopters are expensive and delicate machines requiring heavy maintenance, especially when flying in dusty conditions.

直升机是昂贵而易损的机器，需要精心保养，尤其是在尘土飞扬的条件下飞行时。

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Still, many airline executives suggest they will wait to see how passengers react when flying with pioneers such as Kingfisher.

不过，许多航空公司的高管表示，他们将持观望态度，看看乘坐翠鸟航空等先行者的飞机的乘客反应如何。

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This means it can hover like a helicopter, but when flying forward can reduce the speed of the main rotor because the wings provide part of the lift.

这意味着它能像一架直升机那样作空中悬停，而在向前飞行时，又能降低主旋翼的速度，因为它的一对短翼提供了部分升力。

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She hoped women would have jobs at every level of the industry when flying became a common form of transportation.

VOA: special.2010.05.26

Most injuries happen when flying objects hit people.

VOA: special.2010.05.11

"When flying low in combat, speed is life. Now,from the left,Captain Smith and Captain Cox return to show center at 300 feet and nearly the speed of sound,".

VOA: standard.2009.11.15

Helicopters are expensive and delicate machines requiring heavy maintenance, especially when flying in dusty conditions.

ECONOMIST: Choppers are vital��and hard to find

Try to get a window seat near the front of the plane when flying.

CNN: Sleep tips for the road-weary

The museum said it could not yet confirm when Flying Scotsman was expected to operate passenger journeys.

BBC: Flying Scotsman