But on a recent surveillance flight over the forest frontier in Brazil's state of para, there was hardly a wisp of smoke in the sky.

但在最近一次在巴西帕拉州雨林边界上空的侦察飞行中，空气中竟然连片缕烟丝都没有。

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The Launch and Test Range System includes ground-based surveillance, navigation, flight operations and analysis, command and control, communications and weather assets for space missions.

发射和测试系统包括空间飞行的地面系统任务的监视，导航，飞行操作和分析，指挥和控制，通信和气象资产。

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Rockwell Collins Supplying the communication, navigation and surveillance systems on the C919, as well as the in-flight entertainment system and cabin core system.

罗克韦尔柯林斯公司提供通信，导航和监视系统，还有机上娱乐系统和客舱核心系统。

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On board the aircraft carriers there are typically 70-80 planes for defence, attack, refuelling in flight, jamming enemy communications and radars, and for airborne surveillance and control.

BBC: F/A-18C prepares to launch from the USS Enterprise

Although it was due to fly the friendly skies of Lakehurst, New Jersey in mid-June, Northrop Grumman's usually unmanned surveillance was only just caught floating over the Jersey Shore as part of a maiden flight on August 8th.

ENGADGET: US Army's LEMV spy blimp spotted hovering over New Jersey, may take up cargo duties (video)

The Clyde is described by the MoD as a "highly capable and versatile vessel" with state-of-the-art air and surface surveillance radars, a 30mm gun mounting and the capability to operate a variety of helicopters from her flight deck.

BBC: NEWS | UK | England | Hampshire | Warship HMS Clyde is commissioned