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Vril 7 at Arado Brandedburg '44/'45



 
 
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  #1  
Old November 14th 03, 01:19 AM
B2431
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From:


One "VTOL" suacer that got to the preliminary designe stage was this
Focke Wulf "VTOL"
http://www.luft46.com/fw/fwvtol.html

I have no doubt that the device would work and is superior to the tilt rotor

concept and its troublesome gear boxes. It seems to have ducted a gas
turbines' exhaust to power a large contra rotating ducted propellor in the
center of the "saucer" with the tubine then being
deflected to provide forward propulsion.

Indeed if built today it would be excedingly usefull as unlike a helicopter or

tilt rotor it could manouever along side a skysraper or land in tight spots
free of the dangers of rotor impact.


And do what? The drawing shows a vehicle that would carry a crew of one and NO
payload.

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.

Dan, U.S. Air Force, retired
  #2  
Old November 14th 03, 04:41 AM
Pete
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"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


  #4  
Old November 17th 03, 01:11 AM
The Enlightenment
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Posts: n/a
Default

(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.
  #5  
Old November 17th 03, 05:04 AM
B2431
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Posts: n/a
Default

From: (

(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.



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.

However that is not how the Avro machine worked. See:

http://www.laesieworks.com/ifo/lib/avro-graph02.html

If you poke around the web you will find all kinds duct being used to hover.
You will even find a few that can transition from vertical to horizontal
flight. The closest to being practical I can recall was in the 1960s Boeing
produced on with four ducts mounted on winglets.

Dan, U. S. Air Force, retired
  #6  
Old November 17th 03, 11:06 PM
The Enlightenment
external usenet poster
 
Posts: n/a
Default


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


SNIP

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.



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.

However that is not how the Avro machine worked. See:

http://www.laesieworks.com/ifo/lib/avro-graph02.html

If you poke around the web you will find all kinds duct being used

to hover.
You will even find a few that can transition from vertical to

horizontal
flight. The closest to being practical I can recall was in the 1960s

Boeing
produced on with four ducts mounted on winglets.

Dan, U. S. Air Force, retired


There are a number of ducted fan concepts. The Piasaki flying Jeeps
worked and had advantages but were fuel hogs that had trouble landing
on uneven ground and there were concerns that they were dangerous in
gusty conditions.
http://www.faqs.org/docs/air/avplatfm.html#m4

It seems to me that the Israeli guy (built the prototype in his
apartment and had to knok down the wall to get it out) has adressed
most of the shortcommings of these Piasaki aerial platforms.
http://www.urbanaero.com/Urban_Main.htm

Many VTOL and ducted fan concepts are documented on
http://www.vstol.org/ The 'wheel of misfortune' is interesting and
the Boeing project you refer to is I think the Bell X22A but there
were others such as the Bell model 65 ATV

In reference to the Avro canada saucer:
http://www.faqs.org/docs/air/avplatfm.html#m4

"A wind-tunnel test model and a flying prototype were built. The test
model was sent to the NASA Ames Center in California for wind-tunnel
tests. First tethered flight of the flying prototype was at Malton on
29 September 1959, followed by the first untethered flight on 5
December 1959. Although Frost and his staff recognized that the
Avrocar was inherently unstable and had incorporated an
electromechanical stabilization system, it wasn't up to the job, and
once the Avrocar picked itself up to above chest height and got out of
ground effect, it bobbled around drunkenly.

An improved stabilization system was considered, but Avro was in chaos
due to the cancellation of the "CF-105 Arrow" interceptor program. The
chaos filtered down to the Avrocar program, and the US backers of the
program lost interest. The program was axed in December 1961. Whether
it would have ever flown right remains an open question. "

The "Electromechanical" stabalisation sytem was surely no more than a
single gyroscope and some microswitches mounted on the gimballs to
opperate shutters in the air-stream. A 3 axis multi-input
multi-output non linear or state space controller was probably needed
to achieve rock steady stabillity and that needs to be put together by
specialist control theorotecians.





  #7  
Old November 16th 03, 12:39 PM
The Enlightenment
external usenet poster
 
Posts: n/a
Default


"B2431" wrote in message
...
From:



One "VTOL" suacer that got to the preliminary designe stage was

this
Focke Wulf "VTOL"
http://www.luft46.com/fw/fwvtol.html

I have no doubt that the device would work and is superior to the

tilt rotor
concept and its troublesome gear boxes. It seems to have ducted a

gas
turbines' exhaust to power a large contra rotating ducted propellor

in the
center of the "saucer" with the tubine then being
deflected to provide forward propulsion.

Indeed if built today it would be excedingly usefull as unlike a

helicopter or
tilt rotor it could manouever along side a skysraper or land in

tight spots
free of the dangers of rotor impact.


And do what? The drawing shows a vehicle that would carry a crew of

one and NO
payload.


It has one crew member. It could no doubt carry a warload or cargo in
the ring shaped fueselage or adated for more crew or passengers.



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.


This Canadiarn AVRO device used the coanda induced airflow effect and
a sort of hover-craft effect which is somewhat different to this Focke
Wulf FW-VTOL concept which used a large rotor sised ducted fan in a
lenticular like body.

Most ducted fan lift concepts have worked and seem to have provided
forward speeds twice that of helicopters. A ducted fan of course is
not going to be as effective at providing lift as a full sized rotor.

Better to have a good hovering helicoper and a poor crusing vehicle
than a poor hovering VTOL craft and an average cruising vechicle.
Hence aprt from the Harrier helicopters are the only VTOLs in service.

As I pointed out however such a vehicle might have advantages in
closed approaches in rescues or landings in confined spaces or if
twich as fast as a Helicopter better survivability in battle.

Two vehicles using ducted fans are being built now in the USA and
Israel.

http://www.moller.com/
http://www.urbanaero.com/Urban_Main.htm

They both have a plausible market. (The Israeli one seems the better
to me)


If equiped with an appropriate control system of gyroscopes,
accelerometers and perhaps radar/lasers such a vehicle might be made
to hold station centimeters from a building to rescue people or to
land on someting as small as a tennis court.

The old FW-VTOL concept seems as good as the above two.




Dan, U.S. Air Force, retired



  #8  
Old November 16th 03, 10:09 PM
B2431
external usenet poster
 
Posts: n/a
Default

From: "The Enlightenment"

"B2431" wrote in message


One "VTOL" suacer that got to the preliminary designe stage was this
Focke Wulf "VTOL" http://www.luft46.com/fw/fwvtol.html

I have no doubt that the device would work and is superior to the tilt

rotor concept and its troublesome gear boxes. It seems to have ducted a gas
turbines' exhaust to power a large contra rotating ducted propellor in the
center of the "saucer" with the tubine then being deflected to provide
forward propulsion.

Indeed if built today it would be excedingly usefull as unlike a helicopter

or
tilt rotor it could manouever along side a skysraper or land in tight spots

free of the dangers of rotor impact.

And do what? The drawing shows a vehicle that would carry a crew of one and

NO payload.

It has one crew member. It could no doubt carry a warload or cargo in the

ring shaped fueselage or adated for more crew or passengers.


Look at the fuselage, other that very small spaces everything would have to be
structural, puffer and drive ducts or fuel tanks. In any event the Nazi version
would have required technology not available until the 1960s like computers
and turbinoshaft engines with enough power to be able to divert some bleed air
for forward thrust and control.

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.

snip

Most ducted fan lift concepts have worked and seem to have provided
forward speeds twice that of helicopters.


Name one.

snip

Two vehicles using ducted fans are being built now in the USA and Israel.

http://www.moller.com/
http://www.urbanaero.com/Urban_Main.htm

You have GOT to be kidding. In over 30 years of sucking money from investors
and promising to produce a working prototype " soon" the only thing Moller has
produced other than a bunch of hot air was an unmanned hover in ground effect.

I am not familiar with the other machine you cite, but more power to them.

Dan, U.S. Air Force, retired

  #9  
Old November 16th 03, 11:14 PM
Pete
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Posts: n/a
Default


"The Enlightenment" wrote


Two vehicles using ducted fans are being built now in the USA and
Israel.

http://www.moller.com/


"Built" is a matter of opinion. Has Moller actually flown one of his 'cars'?
No. Tethered, unmanned, hover is as far as it's gotten.

http://www.urbanaero.com/Urban_Main.htm

They both have a plausible market. (The Israeli one seems the better
to me)


"Plausible market"? How so? 'Driving down to your neighborhood vertiport'
and toodling off to work? HA. The average person can't reliably handle 2D
movement, much less 3D.
Why haven't personal helicopters 'taken off'?

Moller VP says this about saucer shapes:
http://www.metroactive.com/papers/me...cars-0302.html
"We still have it here, " Moller VP Jack Allison says about the M200X. "It's
a good test vehicle for part of the technology, but it's not a very
practical vehicle. A saucer's not a very practical shape for aerodynamic
flight and transporting people and things. It's good for takeoff and
landing."

Pics of the M200X and others he
http://www.laesieworks.com/ifo/lib/moller.html


The old FW-VTOL concept seems as good as the above two.


Exactly!

Pete


 




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