Move Over Moller

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 18:59:18 in message
, Larry Dighera
wrote:

I don't see the control system as being that difficult a hurdle.
After all, the Harrier is able to hover with only two nozzles.

I think you will find that the Harrier has four main swivelling nozzles,
the front pair are cold air from the compressors, the rear pair are hot
exhaust from the turbine. In addition it has air driven control jets at
nose, tail and both wing tips. All of then are required for hovering
flight.
--
David CL Francis

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

On Tue, 08 Mar 2005 21:02:35 GMT, David CL Francis
wrote in
::

On Mon, 7 Mar 2005 at 18:59:18 in message
, Larry Dighera
wrote:

I don't see the control system as being that difficult a hurdle.
After all, the Harrier is able to hover with only two nozzles.

I think you will find that the Harrier has four main swivelling nozzles,
the front pair are cold air from the compressors, the rear pair are hot
exhaust from the turbine. In addition it has air driven control jets at
nose, tail and both wing tips. All of then are required for hovering
flight.

I've not noticed any other Harrier nozzles than one on each side.
Thanks for the information. I suppose in theory it would be possible
to hover with only one nozzle.

Recently, Larry Dighera posted:

On Sat, 05 Mar 2005 17:26:33 GMT, "Colin W Kingsbury"
wrote in
. net::

Sure, it might fly, but who wants a machine with the fuel burn of an
old Lear (at low altitude), the maintenance costs of a big Sikorsky,
and the payload of a 172?

[...]

It's a start. It portends the future. It's going to need development
and refinement, but I believe these vectored thrust machines will
eventually be successful in achieving flight and eventually public
acceptance.

I just wonder *where* these things might be operated. Certainly not down
any city street or through any neighborhood?

Neil

On Wed, 09 Mar 2005 02:14:35 GMT, "Neil Gould"
wrote in
: :

I just wonder *where* these things might be operated. Certainly not down
any city street or through any neighborhood?

I know what you mean. And I think you've touched on the cause of
their delayed development: a narrow range mission goals.

I have read that a primary mission goal would be for rescue of
personnel from sky scraper windows where the rotor disk of helos
complicates getting close enough for success. I'm not sure that would
be a viable mission either given the likelihood the down wash would
possibly suck out the glass facade.

The military funded some SoloTech research, so I would expect that the
concept of zooming soldiers around the battlefield or over mine fields
and water has some merit.

The lack of suitable missions, other than sheer joy of operation,
seems to be a significant hurdle.