Hey Fred!
The 20 mph speed increase I observed with the Catto 64 x 62 3 blade is
real (at least on
my 125 hp Soob). Don't forget that you will be pushing an additional 25%
power thru the
blades than any of these units were designed for so even if you find the
perfect prop for a 100 hp 912S, you will be underpropped on your Honda VTEC!
Glenn Crowder
>From: "Fred R. Klein" <fklein@orcasonline.com>
>Reply-To: europa-list@matronics.com
>To: <europa-list@matronics.com>
>Subject: Re: Europa-List: Arplast info please? Was prop balancing (+
> Advert)
>Date: Tue, 15 Mar 2005 13:21:35 -0800 Advert)
>
>
>Brian,
>
>I forward the following info on Arplast props plus some of the info I've
>uncovered in my own prop qwest:
>
> >> - Jerry Davis @ Lyndhurst Touchdown Services, reps for Arplast
>Propellers:
>
> >> this unit is being used in several Europas; blade profiles & twist
>unknown.
> >> PV50 propellers are designed for use on experimental and similar
>aircraft.
> >> They are not certified. There are around 250 propellers fitted to 912,
>912S
> >> and 914 engines. We now offer a constant speed controller designed and
> >> manufactured in the UK. Prices are as follows:
> >>
> >> Propeller less controller is 2700 Euros $3500
> >> Paint option 130 Euros $170
> >> Standard controller is 150 Euros $195
> >> Constant Speed controllers is 475 Pounds $880
> >> Optional manifold pressure sensor is 55 Pounds $100
> >>
> >> All plus shipping. Prices in dollars are approximate. For a CS version
>with
> >> MAP sensor and black blades price would be around $4480 + shipping.
> >>
> >> Propellers are available in Black, Red, White and Grey. For the non
>black
> >> props the backs of the blades are painted matt black with an aerosol.
>This
> >> matt black is not very durable so for the paint option extra the back
>of the
> >> blade can be painted in a two pack Satin black polyurethane paint which
>is
> >> durable. The black blades do not require this option.
> >
> >> best regards Jerry Davis
> >>
> >> Managing Director
> >> Lyndhurst Touchdown Services Ltd
> >> jerry@ban-bi.com
>
>My decision on propellers (as yet undetermined) is being influenced by some
>info and concern about blade design which I share as follows:
>
> > - THE WARPDRIVE BLADES
> >
> > The WarpDrive blade is a quality product w/ many fine characteristics;
> > however, it suffers in a high-cruise-speed situation. All WarpDrive
>blades are
> > from the same mold and blade length is varied by trimming. Consequently,
> > for a given application, it is not possible to optomise and provide the
> > correct amount of blade area, disc area, pitch, pitch distribution etc,
>etc.
> > The design was optimised for 72" to 84" prop diameters, engines in the
>80-100
> > hp range, flying at 100-125 mph cruise speeds. At full length the blades
>have
> > a twist of 20 degrees; when cut down for the 64" dia. Europa
>application, the
> > blade twist reduces to 13 degrees.
> >
> > - quote from Glenn Crowder, Europa pilot, Golden, CO
> >
> >> The twist is important on your application because as you approach the
>fast
> >> part of the flight envelope, the inboard sections of the prop begin to
>go
> >> into beta mode. This means the air is being accelerated over the lower
> >> camber faster than over the upper camber, essentially making reverse
>thrust
> >> (or at least making enough drag to be the main factor in acheiving
> >> equilibium - no more acceleration). For airplanes in the 135 mph
> >> range, a proper design might have about 40 - 50 degrees of twist from
>the
> >> tip to the most inboard definable sections. A Warp, at 64" has about 13
> >> degrees. So, the lack of twist on the Warp and the resulting drag on
>the
> >> inboard stations is certainly slowing you down but there is NO off the
>shelf
> >> design out there yet that can well accomodate your plane.
> >
> > - quote from Stuart Gort, President, PowerFin Props
> >
>
>I queried Airmaster in this regard as follows:
> >
> >> Hi Martin,
> >>
> >> As I've proceeded w/ various threads of enquiry as to prop selection
>for my
> >> Europa XS mono, I've been given some disappointing comments about the
>Warp
> >> Drive blades; namely, that they have insufficient twist which imparts
> >> negative
> >> thrust along the inner portions of the blades when the pitch controller
>sets
> >> the coarse pitch for max. efficiency and fuel economy (i.e., min.
>propeller
> >> rpm) in the higher speed ranges.
> >>
> >> One Europa flyer/owner claims that this drawback of the Warp Drive
>blades was
> >> evident when he switched to a fixed pitch, 3 bladed, 64 x 62 wood prop
>and
> >> achieved a 20 mph increase in speed at cruise, other conditions being
>equal.
> >> (This example did not involve the Airmaster hub, but rather an NSI hub
>w/ WD
> >> blades).
> >>
> >> Do you think this is a fair criticism of the Warp Drive blades?..and,
>if so,
> >> was it something you considered and felt you could live with given the
>other
> >> excellent characteristics of the WD blades?
> >>
> >> Fred
> >>
> >> - hoping to achieve the Europa-advertised 200 mph!
> >
>
> I received the following response from Airmaster:
>
>
> >> Dear Mr Klein
> >>
> >> The issue of blade design is an interesting one and I am sure you will
>find
> >> a variety of opinions on it.
> >>
> >> I do not doubt that the WD design could be improved apon if sufficient
> >> knowledge and money was applied to it. However the performance from
>them is
> >> not as bad as you may have been told.
> >>
> >> I know that Europa have always favoured the WD blades even when they
>had
> >> many other types to choose from. I would question the ability of a
>fixed
> >> pitch prop to gain 20 mph over the Airmaster.
> >>
> >> Tests we conducted with Europa USA using a monowheel 914 with the
>Airmaster
> >> compared to a Whirlwind 2 blade. The two blade was designed
>specifically to
> >> compete on the Europa and so should be as good as it gets.
> >>
> >> There was no reported difference between the two at sea level up to
>5000 ft
> >> (where most of your flying is done) and a few knots at 15000ft due to
>the
> >> Whirlwinds comparatively large blades.
> >>
> >> In all other regards the WD have been outstanding in terms of
>reliability
> >> and wear.
> >>
> >> We may test other blades in the future but for the present we have been
> >> asked to stick with Warpdrive.
> >>
> >> Regards
> >> Martin Eskildsen
> >> General Manager
> >>
> >> Airmaster Propellers Ltd
>
>Brian...I believe but cannot confirm that the twist in the blade design on
>the Arplast prop is greater than that of the WarpDrive blade.
>
>Fred
>A194
>
>on 3/15/05 12:36 PM, EuropaXSA276@aol.com at EuropaXSA276@aol.com wrote:
>
> >
> > In a message dated 3/15/2005 1:02:25 AM Central Standard Time,
> > combined.merchants@virgin.net writes:
> > I then changed my prop for an Arplast PV50 VP prop and the
> > vibration was much worse, so I had a go at dynamically balancing it by
>trial
> > and error by placing washers under the spinner screws and judging
>whether
> > Hi William:
> > Where can I find information on this Arplast PV50 VP? I just Googled it
>and
> > all that really turns up are Europa related sites. It appears that a
>number of
> > Europas may have this baby installed. Is this a 3 blade design?
>Electric?
> >
> > Seeking Europa XS performance information when bolted to a 912ULS.
> >
> > Happy trails.
> >
> > Brian Skelly
> > Texas
>
>
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