The SpaceLiner, which is being developed by the Institute of Space Systems at the German Aerospace Center, could allow passengers to board in Europe, sit back, and disembark 90 minutes later on the other side of the world, in Australia.
Image: DLR
A hypersonic "SpaceLiner" would whisk up to 50 passengers from Europe to Australia in 90 minutes. The futuristic vehicle would do so by riding a rocket into Earth's upper atmosphere, reaching 24 times the speed of sound before gliding in for a landing.
Many challenges still remain, including finding the right shape for the vehicle, said Martin Sippel, project coordinator for SpaceLiner at the German Aerospace Center. But he suggested the project could make enough progress to begin attracting private funding in another 10 years and aim for full operations by 2050.
The current concept includes a rocket booster stage for launch and a separate orbiter stage to carry passengers halfway around the world without ever making it to space. Flight times between the U.S. and Europe could fall to just over an hour if the SpaceLiner takes off — that is, if passengers don't mind paying the equivalent of space tourism prices around several hundred thousand dollars.
"Maybe we can best characterize the SpaceLiner by saying it's a kind of second-generation space shuttle, but with a completely different task," Sippel said.
SpaceLiner passengers would have eight minutes to experience the rocket launch before they reached an altitude of about 47 to 50 miles (75 to 80 kilometers). That falls short of the 62-mile (100-km) boundary considered the edge of space, but even a suborbital flight would allow SpaceLiner to glide back to Earth at hypersonic speeds of more than 15,000 mph (25,200 kph).
Relying on rocket power
The rocket-powered design stands out compared with other proposed hypersonic jets, which feature new air-breathing engine concepts. European aerospace giant EADS previously unveiled a hypersonic jet concept that would rely mainly upon air-breathing ramjets to reach cruising speeds of Mach 4 — faster than the supersonic Concorde's Mach 2 performances but far slower than the SpaceLiner's Mach 24 goal.
SpaceLiner's European project planners say their reliance upon proven rocket technology could allow their vehicle to fly sooner rather than later. They plan to use liquid oxygen and hydrogen rocket propellants so that the rocket engines leave only water vapor and hydrogen in the atmosphere. [Video: How DARPA's HTV-2 Hypersonic Bomber Test Works]
"We will not try to improve the performance of the engine but would like to have it more reusable," Sippel told TechNewsDaily.
The empty rocket stage from SpaceLiner would return to Earth immediately after launch in preparation for reuse. An aircraft could grab the rocket stage in midair, tow it toward an airfield and release it for an autonomous gliding landing.
Chances of survival
But big challenges remain before SpaceLiner can take off. Researchers first must finalize a design shape capable of surviving the intense heat created by gliding at hypersonic speeds through the upper atmosphere. New cooling technologies and improved heat shielding for SpaceLiner's wing "leading edge" could help in that case.
Launching like a rocket rather than taking off like an aircraft means SpaceLiner would remain restricted to suitable launch sites with uninhabited areas down range. The SpaceLiner also would need a careful flight path during its final landing approach — the "sonic boom" shock that accompanies aircraft traveling faster than the speed of sound can damage buildings on the ground at low altitudes.
See what we're tweeting about
8 Comments
Add CommentHmmm, Wouldn't you achieve the kind of economy of scale, that would make such a project profitable, if you designed a single vehicle for both space tourism and supersonic planetary use? Or is there something about the two objectives that is thought to be mutually exclusive?
Reply | Report Abuse | Link to thisglobalism will be long dead at that time. There won't be a demand.
Reply | Report Abuse | Link to thisWill passengers be required to pass a physical? Not everyone can be an astronaut, and many people have health issues, heart conditions for example, that they're not aware of...
Reply | Report Abuse | Link to thisHealth issues aside,the real issue is can it be done at a profit?I think more likely a much smaller craft with 10 to 20 passengers,because the cost of failure would be much lower.The price of a ticket would still be somewhere around75,000 to 125,000 one way.For most who could afford it getting there that fast just wouldn't make any sense.Its more likely that small corporate craft of this size could fly without making a profit.Even then most would not think it was worth the risk,other than the thrill seekers.
Reply | Report Abuse | Link to thisThe giant price doesn't seem to justify the time saved. The cancellation of the Concorde SST shows there just isn't the demand for this commercially. Maybe the Mil could use it for logistics but that's about it I think. Besides, if you need to get from Los Angeles to Moscow in 90 min you're effed no matter what.
Reply | Report Abuse | Link to thisThink of the logistics, you have to fly from (e. g.) New York to the Mojave desert or Cape Canaveral, where you will then board your 2 hour flight to a spaceport outside Sydney from where you will have to get onto another plane to get to Sydney. Where do they suggest to launch and land the things in Europe? Does not sound very practical to me. But of course a fascinating idea and a great concept to ponder.
Reply | Report Abuse | Link to thisi don't see any mention of a secondary propulsion unit, to be used after the booster is finished...without that, the landings would be at least as interesting as the take off's...if there's no secondary unit, why worry about dropping the booster? - why not just carry it along, since the vehicle would only be gliding once the boost phase is done...anyway, go ahead and work it all out - sounds great to me...i'll start saving...
Reply | Report Abuse | Link to thisWhat does it mean "you are effed no matter what"?
Reply | Report Abuse | Link to this