While still some way off, the new SABRE engine technology could allow travel to anywhere on earth in four hours.
Bringing us one giant leap closer to commercial space travel, UK-based Reaction Engines Ltd has recently had the European Space Agency(ESA) verify the viability of their SABRE (Synergetic Air-Breathing Rocket Engine) engine technology. After two decades of research, Reaction Engines executive, Tim Hayter, told a London press conference, "We have made the biggest breakthrough in propulsion technology since the jet engine." This is a bold claim, but given the ESA's response to the technology, it may be spot on.
Current technology uses partially reusable multi-stage launch vehicles, which are quite expensive to create, and portions of which are discarded after a single use. The SABRE-powered SKYLON, however, should be able to circumvent many of those expenses thanks to the hybrid engine, which can operate both in the atmosphere as a regular jet engine travelling upwards of mach 5, or in space as a traditional rocket. "In the past, attempts to design single stage to orbit propulsion systems have been unsuccessful largely due to the weight of an on-board oxidiser such as liquid oxygen, needed by conventional rocket engines," states the Reaction Engines website. The SABRE approach to this problem is to use the oxygen present in the atmosphere, much like existing jet engines. SABRE is apparently the first engine to do this, "This approach enables SABRE-powered vehicles to save carrying over 250 tons of on-board oxidant on their way to orbit," continues the REL website, "and removes the necessity for massive throw-away first stages that are jettisoned once the oxidant they contain has been used up."
While the technology has been deemed sound by the ESA, the reality is that SKYLON still only exists on paper, and is years away from construction. Reaction Engines is currently looking for an additional $400 million in funding over the next 10 years to continue development. While this seems like an exorbitant sum of money, Hayter has estimated the value of the global space market at $300 billion, eclipsing the SABRE funding goal.