Move Over Moller

("Colin W Kingsbury" wrote)
snips clipped
It seems to me that vectored-thrust aircraft face a couple of fundamental
challenges that will not be easily overcome.

First, you have the poor efficiency of turbines at low speed. The ducted
fan
approach will improve this somewhat but if you look at the V-22, it has
HUGE
propellers, more like mini chopper blades. The V-22 may be intended to
spend
more time in hover than a Mollermobile, but I'll side with the machine
that's being flown seriously over the eternal prototype.

Again, the V-22 is the best precedent we have to go on here, and the
evidence is pretty bad. Twenty-some billion spent as I recall and the
things
are still nowhere close to deployment.


The V-22 Osprey project drives me nuts. V-22 Billion!!
(Semper Fi Congressional Industrial Complex)

The 1950's Fairey Rotodyne worked. They even had orders.

It was flying around Europe, hauling people and freight, in the late 50's
and early 60's. This thing was designed over 50 years ago. Can you imagine
new engines, new composites, new engineering concepts, new rotors, new
electronics, etc?

I don't know exactly what the design/mission specs are (were) for the V-22,
but I suspect the Rotodyne came close to meeting some of them, while
outdoing others.

The Rotodyne was successfully flying. Tweak it, and you've got something.
Start fresh and you have $22 BBBBillion worth of nothing. What a sad joke.

Apparently, because of the way the jets on the rotor tips work, there is no
need for a tail rotor. Also, the rotor goes into autogyro mode when the
plane reaches a certain forward speed. The rotor-tip jets kick in for
take-off and landing only. Jet thrust is provided by bleed air from the
turboprop engines, located on the Rotodyne's stubby wings.

Reason I've read for its demise was fear of noise pollution (Right, like a
1st generation 707 wasn't loud? And what about those 2 Harrier jump-jet at
OSH last year?). Another reason I've read for the project's cancellation was
British Govt. inside politics - with Fairey being outside.

http://www.hofstra.edu/CampusL/Cultu...iro_movies.cfm
Fairey Rotodyne movie on bottom of page

http://www.dunnbypaul.net/aircraft/rotodyne/
Rotodyne info

http://avia.russian.ee/vertigo/fairey_rotodyne-r.html
Rotodyne page

http://www.hofstra.edu/CampusL/Cultu...llery20_22.cfm
X-game simulations are fun


Montblack

Small machines using vectored thrust are going to be noisy, no
matter what, and inefficient (how efficient is a Harrier?). Fly-by-wire
isn't cheap, either (what's an F-16 worth?). These small machines are
no doubt possible, if enough money is spent, but what's the market
going to look like for a two-place model that costs $15 million and
gets 1/2 mile per gallon, giving it a 50-mile range, say? And wakes up
half the city? And don't get me started about electric motors and their
weight and the generators needed and all that.
Thrust is most efficient when it's generated by large-diameter
slow-turning props, rotors or fans. Small units have to spin at high
speed, losing way too much power to drag. A 400-hp helicopter makes way
more thrust than a 400-hp aircraft engine and prop. Airliners use big
fans now instead of the old straight turbojets. All of it proves that
small-diameter air movers are not good and unless there's a powerplant
developed that weighs nearly nothing and turns out huge hp at near 100%
efficiency, these little machines will remain a dream, just like
powered flight was a dream until metallurgy and fuels developed to the
point that the Wrights could build an engine that would actually fly.

Dan

On Mon, 7 Mar 2005 at 14:19:31 in message
, Montblack
wrote:
Reason I've read for its demise was fear of noise pollution (Right,
like a 1st generation 707 wasn't loud? And what about those 2 Harrier
jump-jet at OSH last year?). Another reason I've read for the project's
cancellation was British Govt. inside politics - with Fairey being
outside.

Those people who heard one can testify that it was extremely loud. As to
the politics I cannot say. I say 'those people' because I have a memory
of hearing the ear-splitting noise at a Farnborough Air show. But it
could have been the Flying Bedstead. I saw then both but did I see both
of them fly? - not quite sure of this because of it being around 50
years ago and I am now much older. :-(
--
David CL Francis

"David CL Francis" wrote

Those people who heard one can testify that it was extremely loud. As to
the politics I cannot say. I say 'those people' because I have a memory
of hearing the ear-splitting noise at a Farnborough Air show.

If it is the Harrier you are talking about, I can testify to the fact that
they are very loud, having been as close as 75 feet to one in hover. Ear
splitting is more accurate.

But the coolness factor still places it *way* up there. g
--
Jim in NC