Bud is up to his neck in a poop full of testing.
Right now I have the AP332 and 420 in build up in the shop and will be
starting side by side testing. LSA testing is in write up. I figure by
Rough River I may have some data and the new 420 hanging on the front of
my test mule 12AY. So far on the slower planes like the Rans S-6, the
420 is ten knots faster at the 72 inch length and the performance of the
AP420 is better only on the top end vs. the AP332. It appears the
AP420 will tend to have a top end more like the Whirlwind prop or a
little faster. However, the prop pulses across the windscreen on the
Rans are very noisy at the 72 inch lengths. You can see the windscreen
move. It is quite a stump climber. Hopefully, it is not as noisy with
our shorter 64 inch prop.
The AP420 Prop weighs about 20 lbs. Sensenich is a light prop blade by
some standards, but others are still lighter such as the Kiev, Neuform
and other recent designs from the old Soviet Block. They are much
lighter and flexible blades, which means a potential for harmonic
problems. Martin has accumulated quite a stack of test blades and is
methodically going through them.
It is a work in progress as we are adding the AP430 which is a 3 blade,
large ferrule bore hole for the newer hollow core blades.
Warp Drive was not interested in a wider chord blade or a more refined
blade for the shorter lengths. The problem is the initial inertia on
start up with the solid blades. A Wider blade for them means more
torque on the sprag clutch and possibly very expensive engine repairs.
A hollow blade is the way to go, but the Warp Drive is still the
toughest prop. Airplanes are 20,000 compromises flying in close
formation and we really try not to disappoint customers so the testing
continues...
More to follow.
Bud
----- Original Message -----
From: Robert Borger<mailto:rlborger@mac.com>
To: europa-list@matronics.com<mailto:europa-list@matronics.com>
Sent: Thursday, August 19, 2010 5:01 PM
Subject: Re: Europa-List: Seen at Oshkosh
Steve,
I was at KOSH. Did not see the Warp Drive folks. Must not have
wandered through the muck and mire into the right area. Yup, it looks
pretty radical to me.
I did stop at the Airmaster booth and talked to Martin. There was a
nice looking prop with light weight, composite, blades from Sensenich.
Martin said that they were working on both 2-blade and 3-blade versions.
He also said that Bud was testing one of them. I'll be at Custom
Flight Creations in about a week and a half. Maybe Bud will have some
"poop" to share by that time.
Personally, I like the idea of lighter blades. Since the present WD
blades will already push the Europa to near VNE, not much advantage in
going faster. BUT, lighter blades should have lower rotational inertia
and be easier on the gearbox. Maybe allow one to cruise at a lower MP
at the same RPM and airspeed for better fuel economy?
Check six,
Bob Borger
http://www.europaowners.org/N914XL<http://www.europaowners.org/N914XL>
Europa XS, Short Wing, Intercooled Rotax 914
rlborger@mac.com<mailto:rlborger@mac.com>
Cel: 817-992-1117
On Aug 19, 2010, at 1:13 PM, Steven Pitt wrote:
Rumour had it that Warp Drive were in discussions with Airmaster to
develop a new and more flexible propeller in place of the exisiting
installations.
I met with the Warp Drive team at Oshkosh and they agreed to me
publishing the attached photo of their 'work in progress'. Looks radical
to me but no doubt others may have views on whether this is the way to
go.
BTW was anyone else from the Europa fraternity at Oshkosh?
Regards
Steve Pitt
G-SMDH
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