- The agency is experimenting with the
design because the saucer shape has obvious aerodynamic benefits. Tests
on a tiny craft that weighs just 25g have been successful and wind-tunnel
tests on a larger prototype are taking place. The envisaged test spaceship
would measure 16ft across and carry four people.
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- NASA is working on the principle that
craft that are as at home in space as in our own atmosphere will need a
helping hand before getting beyond the pull of gravity. Rather than rely
on tanks of rocket fuel, the agency is exploring means of transmitting
power to ships from the ground to reduce weight " hence a saucer-shaped
craft propelled into space by a laser beam.
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- The concept is not as radical as it sounds.
It had been mooted as a means of launching satellites several years before
Professor Leik Myrabo of the Rensselaer Polytechnic Institute in New York
State began toying with the notion in the 1970s. He has since proved the
concept and is working on a prototype flying saucer for NASA and the U.S.
Air Force.
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- In practice this will mean a spaceship
guided from Earth by a powerful laser. When the craft reaches the edge
of the atmosphere, and the lifting power of the laser dwindles, the energy
source will be used to heat an on-board store of hydrogen fuel. It is expected
that by the time the laser makes the switch from acting as a propellant
to heating the hydrogen, the ship will be on the brink of the atmosphere,
traveling at more than five times the speed of sound.
-
- The on-board fuel source would then be
used to enter space. It would not need to carry huge fuel tanks filled
with liquid oxygen simply to break free of gravitational pull.
-
- The shape of the prototype craft has
a "shroud" around its lower side that focuses the laser light
on a point on the underside of the saucer. This superheats and combusts
the air there, making it act as a jet exhaust that propels the craft into
the air.
-
- Tests have so far been encouraging. Myrabo
has managed to propel his tiny prototype to almost 100ft. A more powerful
laser is to be built to expand the test. He surmises that a 1 gigawatt
laser would be needed to get a full-size craft into space.
-
- Wind-tunnel tests on a scale model of
the 16ft-wide craft have started and further experiments of the laser-based
propulsion system are due to take place later this year. A final craft
is not expected to be rolled out for several years.
-
- After meetings with other aeronautical
engineers, Myrabo is predicting a second, even more futuristic saucer design.
It could be equipped with microwave receivers so that power could be transmitted
to the craft from an orbiting satellite when it is in space.
-
- The ambitious project would require a
satellite to capture solar energy and turn it into a microwave beam that
would be beamed to the flying saucer. As with the ground-based laser system,
reflectors on the craft would focus the microwaves on the side of the craft
opposite to the intended direction of travel. The system could be beamed
down to Earth to help launch the craft.
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- "My goal has been to cut the cost
of getting to space by a factor of 1,000 using a system that is completely
green [environmentally friendly]," Myrabo says.
-
- "The system would require a fully
mature infrastructure to support these vehicles, but it could bring about
an era of airline-like space travel on highways of light."
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- A project involving flying saucers is
bound to create controversy among the conspiracy theorists who claim that
the American government is basing future spacecraft design on captured
alien flying saucers. However, NASA dismisses such talk. It says: "It's
wrong to liken these designs to UFOs because these are certainly identifiable."
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