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From: "Schuricht, Paul, Dr, DFAN" <Paul.Schuricht@usafa.af.mil>
To: Antony Marsh <antony_marsh@hotmail.com>, britdisc@csv.warwick.ac.uk
Subject: RE: Technical Question
Date: Tue, 27 Jun 2000 16:33:20 -0600
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Short answer - It has a lot to do with the shape of the rim of the disc,
Centre of Pressure
location, the fact the disc is spinning (so it acts like a gyroscope and
also has asymmetric 
lift), how worn the disc is, how many trees you've hit and probably some
other things.

Try some disc golf web pages, or try asking on rec.sport.disc, I know the
r.s.d FAQ had
a section on dics aerodynamics, and I'm sure that there will be people there
with far to
much spare time on their hands who will be able to give you a more
comprehensive answer.

Sonic

> -----Original Message-----
> From: Antony Marsh [mailto:antony_marsh@hotmail.com]
> Subject: Technical Question
> 
> Despite being an engineering student, I'm a little puzzled:
> 
> Why do ultimate discs fly straight, whereas "overstable" golf 
> discs fade 
> away to the left (for a right-handed backhand) ?
> 
> Can someone help?
>