I gained a solid 20 mph by dumping my NSI CAP140 3 bladed electrically
adjustable prop
with the Warp Drive blades for a custom designed fixed pitch 3 blade on my
125 hp EA81 powered mono.
Whenever I flew with the NSI, I would be constantly fiddling with with the
pitch control.
It was just adding too much workload to be fun. I really like the fixed
pitch. It is far
smoother than the NSI and since it is custom fitted to my engine climbs just
as well.
The WD blades were designed for a 100 mph max ultralight and have only an
18 degree
twist on a 74" blade. All WD blades are cut down to length from the same
74" blanks. When you cut them down to 64" they have even less twist. A
proper twist for a 150 mph plane is between 40 and 45 degrees. The WD
blades are a good climb type blade but were never designed for higher
speeds.
I do have a slightly longer takeoff roll as I need some speed for the prop
to start to bite but
I fly off a 4700 ft runway so is not an issue for me.
Glenn
Golden, Colorado
USA
>From: grroberts3@juno.com
>Reply-To: europa-list@matronics.com
>To: europa-list@matronics.com
>Subject: Re: Europa-List: Propellers
>Date: Mon, 21 Nov 2005 19:39:56 -0700
>
>
>"The Aviation Consumer" magazine did an article on just that topic in
>August 2005. Bottom line: for aircraft under 250 HP, gains in
>performance were subjective and variable. In general, three blades gave
>better climb, less noise, less vibration, more ground clearance, and
>looked sexy. Two blades produced higher cruise speed on less fuel , were
>lighter, and were cheaper: but not always.
>
>I don't care to defend these conclusions, I'm merely summarizing the
>article.
>
>GRoberts
>A187
>
>
>writes:
> >
> >
> > Propeller Experts !!
> >
> > I wish to upgrade to a CS prop with full feather option, the main
> > reason
> > being the feathering capability. The obvious choice for many is the
> >
> > Airmaster AP332. Now the Woodcomp SR3000 has the same options, and I
> > believe
> > is a lot cheaper. In addition it has the option for a 2 or 3-bladed
> >
> > propeller. My question is this :
> > What are the pros and cons between 2 and 3 blades, apart from the
> > considerable weight saving of 4 kg. Why are we all using 3-bladed
> > Warp
> > Drives ? The Katana, which is a similar but much heavier aircraft
> > uses a
> > 2-bladed CS Hoffmann on a Rotax 912.
> >
> > Any ideas ?
> >
> > Karl
> >
> >
> > =======================================
> >
> >
> >
> >
> >
> >
>
>
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