What are the forces on a tied down glider?

Darryl Ramm wrote:
On Aug 13, 7:55 pm, "bumper" wrote:
"Eric Greenwell" wrote in message

news:x7Mok.925$xv.899@trnddc02...

My observation is the the wind puffs up the covers so they stand
completely off the top and bottom of the wing. In a strong wind, the
covers look like they are inflated to a high pressure, making the wing
look more like a sausage than anything else. My guess is this is a high
drag, low lift "airfoil", but I have no documentation for it.
--
Eric Greenwell - Washington State, USA
My observation is similar . . . except to me, the puffed up covers look like
the thick, high lift wing on a trainer.

I'd feel a lot better about covers in high winds if there were spanwise
fabric tubes sewn in to allow pipe foam insulation to be inserted for full
length spoilers.

bumper
zz
Minden
USA

The standard Jaxida covers look like this in the wind...

http://www.flickr.com/photos/darrylramm/517165653/
http://www.flickr.com/photos/darrylramm/517140648/

(maybe it was really faster than 20 knots in these photos).

Does Jaxida offer a sewn in place to insert a foam tube?

My covers are not Jaxidas, but are similar in design using a lighter
material (a type of Tyvek). They bulge more evenly on the top and bottom
than Darryl's Jaxida covers. Perhaps Darryl could slide one cover off
it's wing to determine if the other wing is lifting or not? It's not so
easy for me to do that because my covers attach to each other, not a
center section like the Jaxidas.

--
Eric Greenwell - Washington State, USA
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