Richard,
I've been able to test the WhirlWind (WW) blades on my Europa with 914 for
the last six months. I find them an excellent fit for the AP332 since the
blades can be swapped out easily.
That said, a new ferrule had to be made to install the WW blades into the
332 hub. No direct cheap swap out I'm afraid.
Performance wise, it is slightly better and lighter than the wide chord Warp
Drive (WD). If you have the narrow chord WD blades they are a whole lot
better.
We are limited in the Europa to 64 inches diameter and of course to the slow
turning Rotax. With only a cruise RPM of 2050 prop RPM and 2500 Climb RPM
and a high speed airplane with a wide performance range we don't see a large
change in performance between the blades. No amount of twist can compensate
for slow prop speed on a geared engine. Propellers fly on torque so there
is just so much you can do.
I've tested the two blade, three blade WD, Sensenich (Sen) and WW blades.
Performance at nominal cruise up to 7500 feet is not a lot different between
the three (3-8 knots). The two blade Sen is lighter (19 pounds) and
noisier. The three blade WD is heavy at 26 pounds and the WW is slightly
lighter and spins faster on start.
Data for the three indicate the WW climbs slightly better (50 fpm) and is
faster than the WD at 7500-10,000 feet by about 5-6 knots at 5000/31 and
about equal at the lower altitudes and lower RPMs. The two blade Sensenich
is slightly slower than the WW (2-3 knots) but equal in climb to the WW
three blade, but it is
noisier. I do like the two blade as it is easier to remove the cowl on a
trigear aircraft with it installed.
The wide chord WD is brutally strong, wears like iron and will mow the grass
on most fields without requiring any cleanup. Chips can be cared for with
epoxy. Typically the WD will go many years before needing blade service.
Each blade costs about $100 US for a complete refurbishment. Then its good
for another ten years. The finish is flat paint and the nickel tape is flat
also, so it's not a classy looking blade with its square tips. The tapered
blades lower the inertial forces during start and I have said "The tapered
blades are
only good for converting fuel into noise as far as I'm concerned", but that
is unfair. They are just slow.
Both the Sensenich and WW have nickel leading edges but have a clear coat
over it so the clear coat tends to wear off in rain and sand (what we have
mostly in Florida). It makes the prop look nasty after a year of hard
flying without
touchup. Of course both of these blades are hollow core (Sensenich) or foam
(WW) so care must be taken if damage is evident.
I must admit my favorite for looks and performance is the WW. My favorite
for engine maintenance and CG is the Sensenich, and if I was operating off
of an unimproved field full of rocks, I'd take the performance hit and fly
the WD.
Jim Butcher is going to test the WW blades against his WD blades on his 914
mono. Then we will
compare notes and publish the data formally.
I've attached a document from my website on propeller testing techniques on
the Europa.
Take a look at the techniques page and down load the pdf.
It always amazes me that folks do not do extensive testing of their
aircraft. I realize that when built straight, this aircraft is nearly
bullet proof so why bother.
That said, it is gratifying to do a 2000 mile cross country in your bird and
only have to put gas in and be able to look at the range you need and simply
adjust the throttle
to get the desired miles per gallon necessary for the winds to flight plan.
This is possible because you have iron clad data on your
aircraft/engine/propeller you personally have tested.
I hope this helps.
Best Regards,
Bud Yerly
Custom Flight Creations.
-----Original Message-----
From: Davids
Sent: Wednesday, October 14, 2015 4:30 PM
Subject: Re: Europa-List: Airmaster Whirlwind blades
Richard I am looking at this at the moment but need some support from the
community
Sent from my iPhone
> On 14 Oct 2015, at 20:12, Richard Holder <richard.holder@outlook.com>
> wrote:
>
> <richard.holder@outlook.com>
>
> Hi All
>
> Has anyone in the UK tried the new Whirlwind blades to fit the Airmaster
> hub ? Great things are promised.
>
> I just don't want to be the first to try them as the paperwork puts me
> off.
>
> If someone has done it already please let me know.
>
> Thanks
>
> Richard Holder
> G-OWWW
>
>
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