British Spaceplane Engine Test Coming in June

"Big Test Looms for British Space Plane Concept"
Mike Wall, Space.com (April 18, 2011 )

"A huge, unmanned British space plane is on pace to start launching payloads into Earth orbit in less than a decade - provided it can pass a crucial engine test in June, its designers say.

"The Skylon space plane - which would take off and land horizontally, like a commercial jet - is still a concept vehicle for now, but it recently passed several rigorous independent design reviews, the British company Reaction Engines Ltd, which is developing the spacecraft, announced Tuesday (April 12).

"Private funding is lined up to see it through all stages of development, culminating with the start of commercial operations in 2020. That funding, however, is contingent on Skylon hitting some key milestones along the way, and a big one looms just a few months off....

"...In its current design incarnation, the Skylon space plane is a spaceship behemoth. It is about 276 feet (84 meters) long and weighs about 303 tons (275,000 kilograms) at liftoff. For comparison, the main truss of the International Space Station – which is the largest spacecraft ever built – is about 357 1/2 feet (109 meters) long and weighs about 408 tons (370,290 kg)..."

It's not the size of Skylon that sets it apart so much as the engines, in the Lemming's opinion.

Reaction Engines (Abingdon, Oxfordshire) has developed a sort of hybrid engine they call SABRE. It's designed to use oxygen from Earth's atmosphere until Skylon is about 16 miles up and going Mach 5. Then the engine switches to burning hydrogen from an onboard tank, like many rockets do now.

Relying on oxygen collected in transit for the first leg to orbit means less oxygen stored in Skylon - making more room for cargo. Mass, actually - but the point is that it's an elegant idea that hasn't been done before.

Hence the test in June.

The Lemming hopes that Reaction Engines succeeds - and suspects that it won't be long before others are designing and building their own spaceplanes.

• "Hypersonic Transports: Not Yet, But They're Coming"
  (March 30, 2010)
• "Hypersonic Vehicles: Waveriders to Space"
  (November 2, 2009)
• "When it's Time to Build Spaceships, People Will Build Spaceships"
  (October 4, 2009)
• "A Freighter Unloads its Cargo: What's the Big Deal?"
  (September 20, 2009)
• "Skylon: Spaceplane for 2019"
  (March 12, 2009)

The Lemming's take on:

• "Humanity in Space: The Next Few Decades "