Has anyone tried an Elippse propeller on a Europa? See article
www.batterson.net/EAA499/Issue77_8-13.pdf which makes some interesting
points about propeller design.
Mike
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com] On Behalf Of Graham
Singleton
Sent: 28 May 2007 10:48
Subject: Re: Europa-List: re:propeller optimization
<grahamsingleton@btinternet.com>
Fred,William Ira
William and everyone
I continue to be puzzled by the Warp Drive prop, which we all know was
designed for slow microlight A/C. Jerry Davis once pointed out that you
need less twist at hi speed, which can only mean that the Warp has the
wrong twist at any speed! (Jerry is UK agent for Arplast)
Thinking for a moment, at the root the blade angle should be nearly
parallel with the direction of flight. At the tip it will be dependant
on speed, diameter and rpm, (of the prop) With a VP prop it will only be
optimised at one particular speed but should be a good compromise for
the speed range.
I haven't done any sums so more than that I won't say at this point.
Graham
William Mills wrote:
> <william@wrmills.plus.com>
the latest Arplast blades PV55 have a slim aerofoil with plenty of
twist (hub to tip) to cope with cruise
> speeds of 120 /130 Kts (about 24 degs is required)
> Regards,
> William
>
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