Hi Graham
I don't disagree that the effect may be more beneficial on a Europa than a
172 and I would certainly try and eliminate as much drag as possible. To do
that you obviously have to address all sources of drag. However putting a
lot of effort into streamlining and increasing the frontal area of a small
fitting may bring only a small net return. One friend swears his A/C goes
2kts faster when he cleans his propeller? must try that one myself.
Jerry
PS Did you know that not only did a Banbi win the Sun N Fun air race for the
last two years (this year at 158kts average) but was also the Airventure cup
2001 Winner of Speed per cubic inch class. Average was 149 Kts over 1000nm.
Normally aspirated !
LTS@avnet.co.uk
www.avnet.co.uk/touchdown
----- Original Message -----
From: "Graham Singleton" <grasingleton@avnet.co.uk>
Subject: Re: Flying: Performance: Speed kit.
> >The main causes of drag are the frontal area and drag from the aerofoils
> >(wings and tailplane). The bits that stick out contribute a little then
> >changing their drag coefficient does not have a big effect.
>
> Jerry,
> I am not convinced by your argument. IMHO with low drag aircraft like the
> Banbi and Europa the interference drag of things like the flap hangers,
> undercart and particularly cooling drag, forms a bigger percentage of the
> total than on more common aircraft like C 152s etc that already have a
> large built in headwind. Consequently the reduction gained with small
> fairings can have a bigger effect than would otherwise be expected.
> Detail improvements like these have an even bigger effect on high
> performance gliders. Wish I was building a Europa with glider wings? Can
> you persuade Christoph there is a significant market for motor gliders?
> Graham
>
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