(B2431) wrote in message ...
From: "Pete"


"B2431" wrote

Next time you are in the Ft. Eustis VA area go look at the saucer shaped
aircraft (Avro?) they have. It could carry 2 men, hover all of 2 or 3 feet
off
the ground and manoeuver rather nicely. Other than low hover it could not
fly
and wobbled a lot. Unlike the Nazi ideas this saucer WAS built and proved
how
complicated things really were. The downward ducted fan concept has been
tried
several times and not one vehicle had the performance to justify
proceeding to
an operational prototype.


I've seen that beast. Looks evil to ride.

Pete


I have seen films of it in operation. It wobbles.

Last time I was in the museum at Ft. Useless, early 1980s, they had a few
really loony devices. The strangest has to be the one man helicopter where the
guy had to stand on a platform ABOVE the rotors.

Dan, U. S. Air Force, retired


Dan,

you say that this AVROCAR VZ-9-AV proved that the 'flying saucer
couldn't work' despite that fact that it did fly albeit only in ground
effect and with a degree of wobble.

The results of the tests were as follows:

http://www.autobahn.mb.ca/~billzuk/F...aucer%202.html
"The results of the testing revealed a stability problem and degraded
performance due to turbo-rotor tolerances. Before modifications could
be achieved, funding ran out with the final flight test program
completed in March 1961. With the problems that the contractor was
facing in the wake of the cancellation of its premier fighter program,
the Avro Arrow by the Canadian government, Avro was unable to continue
the project. "

OK so the engineering problem of turbo tollerances is corrected ( a
cinch for todays wide bodied cowling manufacturers I expect ) and the
stability problems are solved by a gyroscoep based "Fly By Wire"
stability augmentation system.
( an FBW system like this is an of the shelf cinch today )

Why wouldn't it work now?


From what I can see this system should work. An efficient VTOL device
needs large volumes of slow moving air. A helicopter achieves this
with a rotor. A "saucer" like this can do so by sucking in air at the
top and distributing it to a lip at the edge of the saucer where the
high velocity air is converted to low velocity by inducing an airflow.

When in forward fligh the vehicle will have a low drag coefficent, a
very high lift coefficient. It will be extremely unstable with
stability provided by vectoring under FBW control and perhaps the
gyroscopic effect of the central fan. This might make the device very
manoeverable due to low wing loading.