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Stuart Fields
December 28th 05, 06:16 PM
There are several firms offering either plans for, or kits, for homebuilt
helicopters that have little if any supporting actual flite test data. Yet
apparently there are willing buyers out there willing to part with their
money for these subjects of marketing rhetoric. Even EAA gave some notice
of one of the offerings which adds or implies some credibility to the
offering. In this case, the aircraft has demonstrated flight but is not
mechanically capable of autorotation. Am I missing something? Are there
that many people out there that just believe the marketing rhetoric without
having seen a demonstration or having access to an independent test report?
I know that I don't part with tens of thousands of dollars just based on the
advertising.

Steve R
December 29th 05, 03:30 AM
"Stuart Fields" > wrote in message
...
> There are several firms offering either plans for, or kits, for homebuilt
> helicopters that have little if any supporting actual flite test data.
> Yet
> apparently there are willing buyers out there willing to part with their
> money for these subjects of marketing rhetoric. Even EAA gave some notice
> of one of the offerings which adds or implies some credibility to the
> offering. In this case, the aircraft has demonstrated flight but is not
> mechanically capable of autorotation. Am I missing something? Are there
> that many people out there that just believe the marketing rhetoric
> without
> having seen a demonstration or having access to an independent test
> report?
> I know that I don't part with tens of thousands of dollars just based on
> the
> advertising.
>

Frightening, isn't it! :-o

Flyingmonk
December 29th 05, 07:52 AM
Remember the words of PT Barnum?

Shiver
December 29th 05, 08:31 AM
> Flyingmonk > wrote:

> Remember the words of PT Barnum?

Well there is that angle as well.

However..... Perhaps the interest, down payments, etc., show that there
is a viable market pool of people with enough money to enter the
helicopter market at the low end dollar level.

Two hundred thousand for a clapped out whatever may be way out of their
financial ballpark but fifty grand for a kit of brand new parts is
something else.

It appears that in that particular market level that there are people
with both the money and the dream.

Dave Jackson
December 30th 05, 09:40 PM
Stu,

>"....has demonstrated flight but is not mechanically capable of
>autorotation. Am I missing something?"

Re autorotation;

It might be of interest to know that the first production helicopter, the
Flettner FL-282 had a rotor governor. In addition, Igor Sikorsky's chief
rotor designer, William Hunt, invented a rotor governor for the R-5. The
rotor governor provides automatic entry into autorotation.

Perhaps an article on this subject in your 'Experimental Helo' magazine
would be of interest.

Dave

"Stuart Fields" > wrote in message
...

> There are several firms offering either plans for, or kits, for homebuilt
> helicopters that have little if any supporting actual flite test data.
> Yet
> apparently there are willing buyers out there willing to part with their
> money for these subjects of marketing rhetoric. Even EAA gave some notice
> of one of the offerings which adds or implies some credibility to the
> offering. In this case, the aircraft has demonstrated flight but is not
> mechanically capable of autorotation. Am I missing something? Are there
> that many people out there that just believe the marketing rhetoric
> without
> having seen a demonstration or having access to an independent test
> report?
> I know that I don't part with tens of thousands of dollars just based on
> the
> advertising.
>
>

Stuart & Kathryn Fields
December 31st 05, 01:07 AM
Dave: Thanks for the idea for an article. I'll look into that. On the
other hand if there is no collective pitch control available to the blades,
autorotation is going to be at least problematical. --

Stuart Fields
Experimental Helo magazine
P. O. Box 1585
Inyokern, CA 93527
(760) 377-4478
(760) 408-9747 general and layout cell
(760) 608-1299 technical and advertising cell

www.vkss.com
www.experimentalhelo.com


"Dave Jackson" > wrote in message
news:ePhtf.222047$Gd6.115880@pd7tw3no...
> Stu,
>
> >"....has demonstrated flight but is not mechanically capable of
> >autorotation. Am I missing something?"
>
> Re autorotation;
>
> It might be of interest to know that the first production helicopter, the
> Flettner FL-282 had a rotor governor. In addition, Igor Sikorsky's chief
> rotor designer, William Hunt, invented a rotor governor for the R-5. The
> rotor governor provides automatic entry into autorotation.
>
> Perhaps an article on this subject in your 'Experimental Helo' magazine
> would be of interest.
>
> Dave
>
> "Stuart Fields" > wrote in message
> ...
>
> > There are several firms offering either plans for, or kits, for
homebuilt
> > helicopters that have little if any supporting actual flite test data.
> > Yet
> > apparently there are willing buyers out there willing to part with their
> > money for these subjects of marketing rhetoric. Even EAA gave some
notice
> > of one of the offerings which adds or implies some credibility to the
> > offering. In this case, the aircraft has demonstrated flight but is
not
> > mechanically capable of autorotation. Am I missing something? Are
there
> > that many people out there that just believe the marketing rhetoric
> > without
> > having seen a demonstration or having access to an independent test
> > report?
> > I know that I don't part with tens of thousands of dollars just based on
> > the
> > advertising.
> >
> >
>
>

Stuart & Kathryn Fields
December 31st 05, 01:39 AM
Dave: I looked at your site on the Unicopter and Sychrolite and saw the
references to the rotor governor, but couldn't tell just how this device was
supposed to work. I cautiously assume that it senses rotor speed and
collectively adjusts pitch to keep the blade speed at some pre-selected rpm?
I also assume that the pilot would have an override for this feature? Do
you know where I can read up on the use of the governor and why that device
hasn't continued to this day? It seems the R-22s might like to have one if
the downside was not too steep.
An aside issue, you state that the need for yaw control of the Unicopter
would be more like a fixed wing. With the exception of hovering, I find the
yaw control on my helicopter to be less than that required by the fixed
wings that I have flown. e.g. no need to lead the turn with pedals to keep
the ball centered. A lot of the multi rotor systems supporters seem to
think that the use of the anti-torque pedals requires a lot of training. I
did not find that to be true at all. Even in the hover. Are you helo
rated?

--
Stuart Fields
Experimental Helo magazine
P. O. Box 1585
Inyokern, CA 93527
(760) 377-4478
(760) 408-9747 general and layout cell
(760) 608-1299 technical and advertising cell

www.vkss.com
www.experimentalhelo.com


"Dave Jackson" > wrote in message
news:ePhtf.222047$Gd6.115880@pd7tw3no...
> Stu,
>
> >"....has demonstrated flight but is not mechanically capable of
> >autorotation. Am I missing something?"
>
> Re autorotation;
>
> It might be of interest to know that the first production helicopter, the
> Flettner FL-282 had a rotor governor. In addition, Igor Sikorsky's chief
> rotor designer, William Hunt, invented a rotor governor for the R-5. The
> rotor governor provides automatic entry into autorotation.
>
> Perhaps an article on this subject in your 'Experimental Helo' magazine
> would be of interest.
>
> Dave
>
> "Stuart Fields" > wrote in message
> ...
>
> > There are several firms offering either plans for, or kits, for
homebuilt
> > helicopters that have little if any supporting actual flite test data.
> > Yet
> > apparently there are willing buyers out there willing to part with their
> > money for these subjects of marketing rhetoric. Even EAA gave some
notice
> > of one of the offerings which adds or implies some credibility to the
> > offering. In this case, the aircraft has demonstrated flight but is
not
> > mechanically capable of autorotation. Am I missing something? Are
there
> > that many people out there that just believe the marketing rhetoric
> > without
> > having seen a demonstration or having access to an independent test
> > report?
> > I know that I don't part with tens of thousands of dollars just based on
> > the
> > advertising.
> >
> >
>
>

Dave Jackson
December 31st 05, 06:44 PM
Stu;

A gentleman sent me three pages out of William Hunt's book. The pages cover
his patent for this rotor with torque-pitch coupling. He also suggests that
the collective lever could be eliminated.

I will attach the three pages to an e-mail to you.

The technical and anecdotal information on these few pages was so
interesting that the book is now on order.

Dave

"Stuart & Kathryn Fields" > wrote in message
...
> Dave: Thanks for the idea for an article. I'll look into that. On the
> other hand if there is no collective pitch control available to the
> blades,
> autorotation is going to be at least problematical. --
>
> Stuart Fields
> Experimental Helo magazine
> P. O. Box 1585
> Inyokern, CA 93527
> (760) 377-4478
> (760) 408-9747 general and layout cell
> (760) 608-1299 technical and advertising cell
>
> www.vkss.com
> www.experimentalhelo.com
>
>
> "Dave Jackson" > wrote in message
> news:ePhtf.222047$Gd6.115880@pd7tw3no...
>> Stu,
>>
>> >"....has demonstrated flight but is not mechanically capable of
>> >autorotation. Am I missing something?"
>>
>> Re autorotation;
>>
>> It might be of interest to know that the first production helicopter, the
>> Flettner FL-282 had a rotor governor. In addition, Igor Sikorsky's chief
>> rotor designer, William Hunt, invented a rotor governor for the R-5. The
>> rotor governor provides automatic entry into autorotation.
>>
>> Perhaps an article on this subject in your 'Experimental Helo' magazine
>> would be of interest.
>>
>> Dave
>>
>> "Stuart Fields" > wrote in message
>> ...
>>
>> > There are several firms offering either plans for, or kits, for
> homebuilt
>> > helicopters that have little if any supporting actual flite test data.
>> > Yet
>> > apparently there are willing buyers out there willing to part with
>> > their
>> > money for these subjects of marketing rhetoric. Even EAA gave some
> notice
>> > of one of the offerings which adds or implies some credibility to the
>> > offering. In this case, the aircraft has demonstrated flight but is
> not
>> > mechanically capable of autorotation. Am I missing something? Are
> there
>> > that many people out there that just believe the marketing rhetoric
>> > without
>> > having seen a demonstration or having access to an independent test
>> > report?
>> > I know that I don't part with tens of thousands of dollars just based
>> > on
>> > the
>> > advertising.
>> >
>> >
>>
>>
>
>

Dave Jackson
December 31st 05, 07:17 PM
Stu,

> I looked at your site on the Unicopter and Sychrolite and saw the
> references to the rotor governor, but couldn't tell just how this device
> was
> supposed to work. I cautiously assume that it senses rotor speed and
> collectively adjusts pitch to keep the blade speed at some pre-selected
> rpm?

I assume that you are reffering to page http://www.unicopter.com/0575.html,
which is a sub page to http://www.unicopter.com/Governor.html. Actually, it
senses the torque to the rotor. By doing it this way, the application of
more torque from the engine to the rotor will immediately increase the
collective pitch. Conversely, the loss of engine torque lowers the
collective pitch to its autorotative setting. In other words, varing the
torque will vary the collective pitch. You will notice that Hunt's idea has
no provision for collective.


> I also assume that the pilot would have an override for this feature?

Yes, on the idea in my web site, the pilot could still have a collective
stick. A primary difference is that the pilot would have to take action to
stop from going into autorotation, instead of having to take action to go
into autorotation.


> An aside issue, you state that the need for yaw control of the Unicopter
> would be more like a fixed wing.

The UniCopter is a unique rotorcraft, in that the rotors and blades have
'absolute' (actually ~ as close as is reasonably possible to absolute)
rigidity. In other words, the relationship of the blades and the fuselage is
'theoretically' similar to that of an airplane's wings and fuselage. The
technical chalange is the consideration of yaw during hover, which of course
the airplane does not have to consider.


>Are you helo rated?

No. Only fixed wing.

Dave

Flyingmonk
January 3rd 06, 02:47 AM
Shiver wrote:
>However..... Perhaps the interest, down payments, etc., show that there
>is a viable market pool of people with enough money to enter the
>helicopter market at the low end dollar level.

Yes, but who will be the one that will be able to finance a new start
up? I'm thinking of reviving the XROE-1. I think that will sell like
hotcakes.

The Monk

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