I'll mention it to him Wednesday if he's at Racine.
LeRoy Cordes YOLO
Chicago, Illinois
AMA 16974
In God We Trust
On Thu, 26 Jan 2012 21:39:19 -0000 "Yuan Kang Lee" <ykleetx_at_gmail.com>
writes:
> That's very interesting to hear. Can you contact him to join the
> Yahoo! Indoor group?
>
> --- In Indoor_Construction_at_yahoogroups.com, LeRoy C Cordes
> <lcordes_at_...> wrote:
> >
> > Kang, I know I replied to this before but I just confirmed that
> the flyer
> > you asked about in the video was Jeff Annis who Ray Harlan
> recently
> > attributed the pioneering work on the VP for indoors. I knew he
> was a
> > recent returnee to indoor but didn't know about his credentials
> other
> > than his beautiful planes.
> >
> > This is the excerpt from Ray Harlan's email:
> > "The earliest concept of a VP for indoors that I know of is on p.
> 74 of
> > the '37 Zaic yearbook (same page as the torque burner). It is by R
> Hammer
> > and uses a compression spring and bent wires through the prop hub
> to
> > effect what looks to be decreased pitch with increased motor
> tension.
> > Perhaps Zaic didn't draw it correctly.
> >
> > However, the real pioneer of workable VP props was Jeff Annis. He
> > puplished the paper "Torque Variable-Pitch Propeller" in the 1975
> NFFS
> > Symposium. It shows a mechanically workable design employing the
> torsion
> > spring characteristics of the prop shaft. He had tested it prior
> to
> > publication and had found 15-30% better duration over a flaring
> prop in
> > low ceilings.
> >
> > It took quite a while to lead to better designs of the VP prop.
> The Brits
> > tried at the '80 WCh, using essentially the Annis design, but
> couldn't
> > get it working well (see Aug. '82 INAV). Jim Richmond introduced
> his VD
> > prop in'84 in Chicago and used it at the '84 WCh where he won the
> contest
> > with it. After a flurry of activity with VD props, only two fliers
> were
> > successful with them - Jim Richmond and Rich Doig. Attention
> returned to
> > VPs. Ron Higgs tried one with a spiral spring in '85 and set a Cat
> I
> > world record. At this point my collection of INAV is a bit thin. In
> Dec
> > '90 Bob Randolph set a Cat I record with a VP prop that looks much
> like
> > the classic Banks/Brown design. The prop doesn't use a preload
> adjust
> > screw, just a high limit screw (May '91 INAV). I don't know who
> was
> > first. I thought it was Cezar Banks who finally developed a
> compact wound
> > torsion spring design. Steve Brown made the technology accessible
> with
> > his excellent article on how to build a VP in the Oct '96 issue of
> INAV.
> > The current VP designs are only small variants of this design."
> >
> >
> > On Thu, 19 Jan 2012 19:48:03 -0000 "Yuan Kang Lee" <ykleetx_at_...>
> > writes:
> > > Nice to see more F1D's flying. May I ask who were the F1D
> fliers?
> > >
> > > -Kang
> > >
> > > --- In Indoor_Construction_at_yahoogroups.com, "icefishdiced"
> > > <icefishdiced_at_> wrote:
> > > >
> > > > Here are the videos I took in December
> > > >
> > > > http://www.youtube.com/watch?v=NssKBs1d8rY
> > > >
> > >
> > >
> > >
> > >
> > > ------------------------------------
> > >
> > > Yahoo! Groups Links
> > >
> > >
> > >
> > >
> > >
> >
> >
> >
> > LeRoy Cordes YOLO
> > Chicago, Illinois
> > AMA 16974
> > In God We Trust
> > ____________________________________________________________
> > 53 Year Old Mom Looks 33
> > The Stunning Results of Her Wrinkle Trick Has Botox Doctors
> Worried
> > http://thirdpartyoffers.juno.com/TGL3141/4f216bbb85146198b6m03vuc
> >
>
>
>
>
> ------------------------------------
>
> Yahoo! Groups Links
>
>
>
>
>
LeRoy Cordes YOLO
Chicago, Illinois
AMA 16974
In God We Trust
____________________________________________________________
53 Year Old Mom Looks 33
The Stunning Results of Her Wrinkle Trick Has Botox Doctors Worried
http://thirdpartyoffers.juno.com/TGL3141/4f24150baffac1d34fm03vuc
Received on Sat Jan 28 2012 - 07:32:51 CET