Re: Giant Inflatable Antennas in Space

Alan Anderson (aranders@kosepc01.delcoelect.com)
Mon, 22 Jan 96 09:22:54 EST

djmullen@facstaff.wisc.edu (Dave Mullenix) writes:
>Does anybody know the inclination for this flight?

I believe the May SPARTAN flight will be near the minimum inclination
for a KSC launch, about 28 degrees.  Not favorable for many of us.  I 
might just take a trip south that week!

>I've often wondered what would happen if you took two H-U-G-E sheets
>of mylar, aluminized one of them and then locked them both into a giant
>embroidery hoop and pumped a little air in between them.  Does anybody
>know how to calculate whether it's possible to inflate the aluminized
>sheet into a parabola this way?

Yes, that's exactly what they're doing.  For inflatable antennas like 
this, the "embroidery hoop" you mention is usually designed as a very
skinny inflatable donut around the edge of the structure, pressurized 
enough to hold its shape against the *slightly* pressurized lens shape
in the middle.  The mylar sheets for this experiment were extremely 
carefully fabricated to yield the desired shape when inflated.

--------------------------------------------
Alan Anderson              Delco Electronics
                    Remanufacturing Services
        Test Equipment System Software Group