Glen, Not wanting to quibble with your central message, but the Kremen prop
certainly doesn't have Warp drive blades, and in fact has wooden blades
coated with moulded carbon fibre. The Kremen SR2000 Drives my 914 mono
comfortably at 140 kts at low altitude at 100% power Regards, David Joyce,
G-XSDJ
----- Original Message -----
From: GLENN CROWDER <gcrowder2@hotmail.com>
Subject: Europa-List: Europa props for Subaru
>
> >Hey Tom!
> > The problem for me (and also for any Warp Drive users on higher
> >performance aircraft) is that
> >the Warp Drive blades do not have enough twist to be efficient at (or
> >allow) higher speeds.
> >Every propeller has a designed in "pitch speed" that it is most efficient
> >at.
> > The WD prop was originally designed as a prop for ultralight aircraft.
> >Ultralight aircraft are typically
> >too draggy to go faster than 100 mph. It is a very fine propeller for
this
> >application and for speeds
> >up to about 135 mph. Higher speeds than this require a large amount of
> >pitch in close to the
> >hub to avoid going into reverse thrust in this area. The WD is very
> >efficient at its designed speed
> >but it is a one size fits all approach. One can obtain higher
performance
> >(at least at higher speeds)
> >by designing a prop with more twist. At the same time, you need a wider
> >blade to absorb higher
> >horsepower.
> > As far as the Airmaster goes, I'm sure its a very fine propeller, but
it,
> >the NSI CAP 140 (which I
> >have), the Kremen and others all use the WD blades. I think the Arplast
> >uses their own blades.
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