Many countries, including Australia, Britain and Canada, have privatised air-traffic services or turned them into state-owned firms.
许多国家,包括澳大利亚、英国和加拿大,已经私有化的空中交通服务或转为国有企业。
Nav Canada, a non-profit firm that has long managed Canadian airspace, has costs per flight hour of $340 compared with the FAA's $450.
加拿大导航局,一家长期管理加拿大领空的非盈利公司,每小时飞行费用为340美元,而联邦航空局的450美元。
Replacing old radar-based methods with accurate satellite navigation and better digital communications is a particular priority.
旧的基于雷达的导航方式被精确的卫星导航和更好的数字通信取而代之,这是一个特别的优先项目。
Aircraft using satellite navigation can be safely spaced more closely together, which permits many more planes to be in the air at the same time.
使用卫星导航的飞机可以更为紧密却安全相隔,同时允许更多的飞机在空中飞行。
Digital systems also provide data links to control centres and to other planes by regularly broadcasting an aircraft's identification sign, its position and course.
数字系统还通过定期广播飞机的识别标志、位置和航线,向控制中心和其他飞机提供数据链接。
This would allow “free routing”, which means pilots can fly directly to a destination, rather than follow established airways, which often zigzag around.
这将允许“自由飞行”,这意味着飞行员可以直接飞到目的地,而不是遵循既定的航线,往往曲折前进。
The president's proposal might even speed a move towards “virtual” control towers in low-rise buildings, which can replace towers physically located at airports.
总统的提议甚至可能加快向低层建筑中“虚拟”控制塔的发展,以取代在机场设立的物理塔。
The virtual versions are fed live video from airfield cameras.
虚拟塔台是由机场摄像机提供的实时视频。
Proponents argue that they are both safer and around 30% cheaper to operate.
支持者认为,它们更安全,运营成本低30%左右。
Virtual towers can look after more than one airport.
虚拟塔可以兼顾不止一个机场。
One in Norway is set to supervise 32 airports, some of them in remote areas.
在挪威设置的一个将监督32个机场,其中一些在偏远地区。
The European Union reckons such innovations will allow three times as many flights to be handled in the region and save airlines some 9bn euro ($10bn) a year.
欧盟认为,这些创新将允许在一个区域处理三倍多的航班,每年为航空公司节省90亿欧元(100亿美元)。
It also, optimistically perhaps, predicts that on average aircraft will land within one minute of their scheduled arrival time.
它还乐观地预测,平均飞机将在预定到达时间的一分钟内降落。
That would count as a miraculous improvement for anyone, let alone America's weary airport warriors.
这对任何人来说都是一个奇迹般的进步,更不用说美国疲惫的机场工作人员。
Mr Trump, though, may struggle to get the proposal through Congress.
然而,特朗普先生可能很难通过国会的提议。
A similar plan got stuck last year, despite being backed by most airlines and the air-traffic controllers' union.
去年,尽管大多数航空公司和空中交通管制员工会都支持这一计划,但类似的计划还是被搁置了。
At least the president can dodge the queues: Air Force One flights get special clearance.
至少总统可以避开排队:空军一号航班已得到特别许可了。