Re: Current airship project



Hi Pat,

> There's also something to be said for rapid-prototyping, as it quickly lets
> ideas bounce around and cross-pollenate different people.

I agree, is there a brainstorming mailing list, message board or IRC channel?

>  How is it inflated? I thought it was helium inside, not just regular air,
>or do you have a helium bladder inside of the main body? Seems like the
>helium would be pressurized, and wouldn't need a fan to inflate...

The purpose of this model was to test how it flew without a lifting gas. I can't
use lifting gases for airships that I can't recompress or liquefy because a
design requirement is that I have to be able to fit everything back in my
apartment afterwards. This afternoon I tested it outside and it's unstable in
pitch. I believe the reason is that the center of lift is ahead of the center of
buoyancy. The center of lift is about 30% of the way along the chord of the
airfoil; since the balloon is symmetric, the buoyancy is 50% of the way along
the chord, so when the airship speeds up, it either pitches up or down. I
believe a large wing at the rear would balance this by bringing the center of
lift to the center of the airship; but, this would add weight and complexity,
which is what I tried to avoid by modeling blimps instead of aircraft. Because
of this problem, I'm going to try out a pure lifting black airship, the lifting
gas being solar heated air. For propulsion, I'll try to tap the convection
currents around the balloon using a wing at the top.

> "Weird Stuff" used to be the place to go, but has
>gone down in quality the past few years. "HalTed" is now the place that
>seems to get most mention from techno-geeks. Thousands of fans, parts,
>chips, diodes, etc. 

Thanks for that info, there's a small electronic store in Vancouver; but, its
selection is limited and I'll probably need more soon.

Cheers,
Enrique


-- 
Get your firstname at lastname email for FREE at http://NamePlanet.com




This archive was generated by a fusion of Pipermail 0.09 (Mailman edition) and MHonArc 2.6.8.