Jean-Paul,
Here are some figures that I measured earlier this year for a 912S Europa
using a 1600mm (63") diameter 130mm chord Arplast Ecoprop in place of the
64" wide chord Warp Drive (which had been set to 20.5 degrees at the tip).
The Ecoprop propeller came off a BanBi Club (which is the version with
longer wings than the normal (UK) BanBi) and for which direct performance
figures were available. So, to compare with the Club, the propeller was set
up at the same pitch as used on the Club
The BanBi performance figure is shown first, with the Europa figure
following in brackets (...).
Blade set at 20 degrees at the tip (no spinner on the Europa):
Max static was 4400rpm for both aircraft.
128 knts tas at 75% (130knts tas)
149 knts tas flat out (154knts tas 5500rpm)
1250 FPM (1200)
17 lph at 75% (16)
The results are the same within measurable error, except that the Europa was
faster!
The 20 degree pitch setting is OK for a 500m strip but for my short (<400m!)
strip and
fully loaded I needed to fine the prop to 18.25 degrees. Which then provided
almost identical take-off performance to the Warp Drive that I had on
previously, except that
fuel burn was 5 to 7% less with the Eco and vibration was reduced.
The Ecoprop does not "constant-speed" as well as the Warp Drive, so has a
narrower operational speed range, meaning more compromise for climb against
cruise performance.
The Ecoprop 130mm chord possibly has a little too much blade area for the
912S and could be better suited to the 914. I have not tried the 110mm chord
Ecoprop.
If I had the choice of the Warp or the Eco I would probably go for the
Eco. If I had a longer airfield I would definitely have the Eco.
Hope this is of use to you.
Duncan McF.
----- Original Message -----
From: "jpg12305" <jpg.comm@laposte.net>
Sent: Wednesday, July 16, 2008 6:47 PM
Subject: Europa-List: Prop advice fixed pitch - Warpdrive or Arplast ?
>
> My current prop is the standard 3 blade Warpdrive, but unfortunately
> shortened in its early life due to a ground encounter.
> Diameter is reduced to about 58", which (I assume) reduces significantly
> as well its efficiency.
> In order to revert to proper performance I am considering the current
> alternative (VP not being an option due to cost and weight) :
> - purchase new blades from Warpdrive (cheap and straightforward)
> - replace with an Arplast Ecoprop. From misc readings it looks better
> designed than the Warpdrive, question being if the extra performance
> worths the extra cost.
>
> Engine is a 912ULS.
> Has anyone gone through such change ?
>
> Jean-Paul
> Europa monowheel 332 - France
>
>
> Read this topic online here:
>
> http://forums.matronics.com/viewtopic.php?p=193137#193137
>
>
>
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