Jeff Findley wrote:
[...]
HL-20 (click on the picture)
http://grin.hq.nasa.gov/ABSTRACTS/GPN-2000-001923.html

Here's an old page with a 3-view drawing of HL-20
http://www.friends-partners.org/part...s/graume58.htm

Bigger is better:
http://www1.dfrc.nasa.gov/Gallery/Graphics/HL-20/Large/EG-0054-01.gif

/dps