Fred and Frans, may I humbly refer you to the following link with regard to
prop choice etc
After going through this article I am opting for a smaller 4 blade prop,
probably around 60 inches.
http://www.eaa.org/experimenter/articles/2009-02_elippse.asp
-----Original Message-----
From: owner-europa-list-server@matronics.com
[mailto:owner-europa-list-server@matronics.com]On Behalf Of Frans
Veldman
Sent: Saturday, 16 May 2009 6:39 AM
Subject: Re: Europa-List: Tri-gear wheel fairing
Fred Klein wrote:
> May I ask what your prop diameter is?
1720mm (that is 67.5").
I have choosen this prop for optimum cruise performance. Large diameter
= high efficiency. 2 blades versus 3 blades = slightly smaller take off
performance, but above 70 knots much more efficient.
And, last but not least, the inner section has very much twist. Again,
during the early stage of the take off this inner section probably
stalls, but at higher speeds it produces lots of thrust. The inboard
section of conventional props most likely produces no thrust a cruise
speeds, or even negative thrust.
Of course, all of this is so far still theoretical. Once I'm finally
flying, I will collect some performance data.
--
Frans Veldman
Checked by AVG - www.avg.com
17:54:00
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