Re: [Phys-l] football orientation in flight ERRATUM

[John Denker <jsd@av8n.com>]

On 05/21/2008 10:19 PM, I wrote:
 
> Disclaimer: This is probably quite a complicated phenomenon.  It is very, 
> very easy to get the wrong answer in situations like this.

I got that part right.  I should have quit while I was ahead.

> Having said that, here's the first hypothesis that occurs to me, and it seems 
> to fit the facts.

Actually my hypothesis does *not* fit the facts.  I got the direction
wrong on the Magnus force, and therefore (unless I made ANOTHER mistake)
my previous conclusion was diametrically wrong.

When correctly analyzed, the effect I identified makes a _negative_
contribution to the angle-of-attack stability.

I have no idea how to explain the observed stability.  It is easy to
guess that some other effect makes a larger contribution in the direction
of positive stability ... but I have no idea what effect that would be.

Sorry for causing confusion.

============

The following reference is not much help, either:
  http://www.blackwell-synergy.com/doi/abs/10.1046/j.1460-2687.2002.00106.x