SierraMike

The 70hp ZO 03A? Why? Building an ultralight? http://www.zoche.de/specs.html

Marc, Ron, Waiter, Thanks for the great explanations. It makes sense now.

Marc, or anyone else, I have a few follow-up questions for you. Several years ago I got an open water scuba permit. I was surprised at that time to find out that scuba tanks hold regular pressurized air, not oxygen. Lately I have read a lot about oxygen for aviation applications and have been a little surprised to find that it must be oxygen, not just pressurized air. I really don't understand the reason it's OK to breathe pressurized air on a comercial jet, on a Lancair or in a scuba tank, but not out of an aviation bottle. Can you elaborate? Also, on the Cozy, is the reason it can't be pressurized because (a) too many holes, it's impossible to seal, (b) the structure isn't built to withstand that type of outward force, © the materials (foam vs. molded Lancair), (d) some combination of the above, (d) none of the above, something else? Thanks, Steve