Try this:

http://promolife.com/products/usonic3.htm

Uses ultrasound to scare dogs off, or if you want
some comedy value put of it:

http://www.smarthomepro.com/6120.html

similar thing but uses water.


Failing that, just watch Home Alone for a few ideas
(paint cans n strings or heated doornobs anyone? ;-)
)

Or just tie a torch to a 12-guage and get a rotating
bar stool..... ;-D (Think a buckshot lighthouse)

At 16:30 15 April 2005, wrote:
Here's some pictures of damage caused by dogs on Lake
Elsinore Soaring
Club's 233 fleet. Not a pretty sight. Anyone have
any ideas on how to
discourage this dog behavior. We believe they are
chasing rabbits that
have crawled into the gliders through the wheel wells.
__Mike

http://www.soarelsinore.org/damage/