It's provoking more questions about the planes design and what Boeing has told the airlines.

这引发了更多关于飞机设计和波音公司告诉航空公司的问题。

The idea was to put new, powerful engines designed for transport aircraft into planes designed to carry passengers.

这个想法是将为运输机设计的新型、强大的发动机安装到客机上。

It was introduced as a major, new replacement for outdated passenger planes designed during times of the Soviet Union.

该机型是作为苏联时期设计的过时飞机的主要全新替代品而推出的。

One theory is that it is a spy plane, designed to catch savvy targets that know how to go to ground when spy satellites—which have predictable orbits—are overhead.

有一种说法是X-37是一架间谍飞机，旨在捕获各种精明的目标，这些精明的目标发现间谍卫星（有可预见的轨道）位临上空时，能够知道如何隐蔽自己。

An alternative opportunity for electrification lies with small fixed-wing planes designed to transport a few dozen passengers over distances of a few hundred kilometres—for instance, between nearby cities.

电气化的另一个机会在于小型固定翼飞机，其设计用于在数百公里的距离（例如在附近城市之间）运输数十名乘客。