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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