In glide mode:
and back on the ground...
Posted on 05/11/2004 7:13:43 PM PDT by vannrox
Europe took a step towards creating an unmanned space shuttle on Saturday when a prototype landed autonomously after a test flight in Sweden.
The shuttle prototype, called Phoenix, is one of several proposals for a European reusable launch vehicle (RLV) planned to cheaply ferry satellites into orbit by 2015.
In Saturday's trial, Phoenix glided to a perfect landing 90 seconds after a helicopter released it from a height of 2400 metres. The prototype is being used to test ways of landing without the intervention of human controllers. Phoenix uses cues from GPS satellites, radar and laser altimeters, as well as pressure and speed sensors.
"I was there and I had tears in my eyes," says Mathias Spude, a spokesman for aerospace company EADS Space Transportation, which built Phoenix. "We were all under enormous pressure and for us Europeans it was a fantastic moment to witness. It landed three centimetres from the middle of the runway, which is not too bad."
Hopping into space
Phoenix will be released in three more tests over the next two weeks. The first will repeat Saturday's flight but the next two will test "more demanding" landings, in which the craft will be dropped from a different angle or orientation to the landing strip. If all goes well, the next target will be to release the craft from a height of 25 kilometres within three years.
Phoenix is seven metres long and has a wing span of four metres, making it one-seventh the size of a proposed RLV named Hopper. This would launch on a sled running on a four-kilometre-long track at Europe's space base in French Guiana, accelerated by either magnetic fields or steam.
At a height of 130 km, the vehicle would fire an expendable rocket to place its satellite payload into orbit. It would then "hop" down to an island in the Atlantic Ocean and be taken back to French Guiana by ship.
Spude says a reusable launch vehicle like Hopper could halve the cost of sending a satellite into orbit, which now stands at $15,000 per kilogram of payload.
Officials of the European Space Agency (ESA) agree. "All of us have this feeling that reusing the launcher is going to make the launch cheaper," says Luisa Innocenti, ESA's future launchers technology coordinator. "[Imagine] throwing away an airplane after each flight. That's what we do when we launch satellites."
Expensive maintenance
The only reusable launch vehicle in recent use is the US space shuttle, which has been grounded until 2005 and is scheduled for retirement in 2010.
But the shuttle is based on decades-old technology and is very expensive to maintain, Innocenti told New Scientist. "We do not want to end up in the same situation as the shuttle, where they did a fantastic job but which proved so costly to operate that you cannot sell it [for satellite launches]."
ESA's plan is to select a single RLV design by the end of 2005 and to build it by 2015 or so. Competing with the Hopper is a class of "two-stage to orbit" designs, in which one or both rocket stages of a launcher are reusable.
The landing technology tested on Phoenix will also be incorporated into another re-usable vehicle called Socrates. This is not intended to reach orbit but to be capable of flying at 10 times the speed of sound and of turning around very quickly between flights.
ESA is not currently planning to send astronauts on any future RLVs. "But nobody excludes a man-rated version in 40 to 50 years," says Spudes.
Sheesh...talk about polluting the galaxy. That violation of the Prime Directive will REALLY PO Picard!!
What they really need to do is deal with property rights is pace and open it up to private industry and commerce. Only them will we see meanngful "resuable" technology take off.
In glide mode:
and back on the ground...
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