Conventional jet aircraft are all very well and good if
you
like that kind of thing, but they need runways to take off
from and (if they are to be reused) to land on.
Doughnuts, on the other hand, are lovely but are not
viable
as a means of transportation.
It should be evident, therehence,
that here are two
technologies waiting to be merged.
The doughnutoplane consists of a single circular wing,
not
unlike (in fact, one could say, like) those flying ring style
Frisbee-type things.
Supported in the middle of the central hole are five
conventional jet engines. Their intakes (clustered in the
centre) are fed from a single manifold which opens
upward, so that they suck air downward before hurling it
outward to wash over the circular wing.
As the engines are brought up to speed, lift is generated
partly from the ferocious suction of the central jet
intake,
but also from the jet exhaust being directed over the
circular wing. As a result, the whole structure rises
majestically and, above all, vertically from the ground.
Once at a safe altitude, differential throttling allows the
doughnutoplane to transition into something
approximating normal flight. Landing, obviously, is the
reverse procedure.
The present prototype is some 124 feet in diameter and,
at
lift-off, has barely twice the fuel consumption of a fully-
laden 747.
It has not, obviously, been possible to include passenger
or
freight space in this prototype, but its VTOL capabilities
are impressive, as is its ability to clear large landing
areas
of snow, dogs and light aircraft.