奇速英语

超快速航空飞机不久将面世，它有哪些优势呢？

A new airplane may soon be able to travel into the space at more than five times the speed of sound.
      A project by the aerospace company Boeing is making progress. Boeing will finish advanced design work for an experimental space-plane. The experimental space-plane is called the XS-1, or the “Phantom Express”. It would be operated without a human pilot.
     The goal of the project is to make it easier to reach low earth orbit, between 160 and 2,000 kilometers above the surface of the earth. For example, the space-plane could be used to send a satellite into the space very quickly. Now, a lost satellite might take months to replace.
     By 2020, the project could make it possible to use one of the XS-1 vehicles 10 times within 10 days. The Phantom Express space-plane would reduce the cost of sending things into the space to one tenth of today. And the low cost would make them possible "on demand".