Flying Saucers Come Home
With all these advantages, circular
aircraft should be commonplace by now. So where are all the flying saucers?
Despite the benefits, the technology has long been hampered by major drawbacks.
The biggest challenge is that round airplanes are highly unstable because they
don’t employ the conventional aerodynamic systems—specifically, lift-generating
wings and both vertical and horizontal stabilizers—that usually keep aircraft
airborne. “If a plane is moving through the air at a high enough speed,
aerodynamic forces can be used to stabilize it,” says Paul Moller, the
president of Moller International. But VTOL craft, which must become airborne
with zero forward momentum, need another way to generate lift and achieve
stability. To overcome
this obstacle, Moller’s M200G uses its propulsion system to stabilize itself.
The craft moves using eight small ducted fans, each powered by its own
Wankel-style rotary engine, that lift the M200G into the air and push it
forward, backward and sideways. Varying the thrust from the fans also provides
stability—for example, a little extra thrust from the right-side engines
prevents that side of the craft from dipping. Using multiple inertial sensors
and accelerometers, an aircraft-stability computer constantly monitors the altitude
of the craft and sends commands to the engines to adjust thrust in each fan up
to 400 times per second, maintaining stability. The aircraft is constructed of
ultralight materials such as aluminum and fiberglass, which increase the
vehicle’s strength and maximize the engines’ power. With a
starting price of $90,000, the M200G will initially be a toy for the rich. It
will be limited to flying below 10 feet, eliminating the need for Federal
Aviation Administration certification of each pilot. Eventually, the company
hopes to offer low-cost aircraft. “Artificial stability systems will get better
and cost less in the future,” Moller says, “allowing us all to be able to
afford strange and wonderful new flying machines that defy conventional
aerodynamics.” Flying saucers, it turns out, may be just the beginning.
They won’t take you to space, but they might just be worth the long—very
long—wait
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