Story highlights Reusable spacecraft passes tests, approaches flight readiness

Skylon promises cheap, frequent travel into orbit and deep space

Could also allow exoplanet exploration and colony construction

(CNN) More than half a century after Sputnik, space travel remains shockingly wasteful. Every rocket we launch at the cost of hundreds of millions of dollars can only be used once and completes its mission by falling to Earth in pieces. This disposable design has scarcely advanced since the 1960s.

British engineer Alan Bond has been developing a new concept for over 30 years, and is now on the verge of achieving it. His Skylon "spaceplane" design is intended to withstand multiple uses and requires minimal repairs and turnaround time, so it can function as a rapid response unit for space missions, and go far beyond the existing horizons.

"The intention is to replace existing rockets," Bond says. "The technology we are working on would enable more frequent and reliable missions by large factors."

Central to the design is a HOTOL (Horizontal Take Off and Landing) system similar to a regular plane -- albeit from a much longer runway -- so that the craft returns intact. Beyond this, Bond's team at Reaction Engines Ltd. has invented multiple new technologies, most crucially an ingenious concept engine, the SABRE (Synergistic Air-Breathing Rocket Engine).

While existing rockets carry several heavy fuel tanks that are worked through and jettisoned over the course of the journey, SABRE powers the craft from a single chamber carrying liquid oxygen and liquid hydrogen. It minimizes the load by taking in oxygen from the atmosphere during the ascent, which is cooled and and combined with hydrogen to make fuel. Once the craft reaches an altitude of 28 kilometers the engine converts to using the stored liquid oxygen.