Helium bubble addon?

Cameron makes a Roziere balloon. There was a Chrysler Challenge race across the Atlantic a few years ago using identical systems.

What I had in mind was something to convert my friend's Cameron O-90 into a Roziere type of craft. Buying a new balloon is not possible, but an add-on might be.

Well, I conceptualized something exactly like that two weeks ago. My original idea was to build a 9000 cubic foot hot air balloon for a 'first balloon' project but soon I scrapped that idea for lack of nylon and the need to make a dropcloth with the nylon I already have. My next (and better) idea was to use the 9000 cubic foot hot air envelope and a net of helium balloons attached to the top of the envelope around the equator. The net would be lightweight nylon and hold in the helium balloons (which would provide the majority of the lift of the system). The hot air envelope would give the extra lift needed to get off the ground and would also be used as 'virtual' ballast. I'd be strapped into a parachute harness with a ten gallon propane tank hung from the harness (it works that way, trust me). Of course I'd also have extra ballast hung from the harness as well. Well, I've stopped construction of the 9000 cubic foot balloon for the reasons mentioned above but will continue to pursue this concept in the future when I have access to the resources. I'll probably use a 10000 cubic foot envelope just to make it an even number and to give a little more lifting power. I'm always on the lookout for the materials I'll need in the future.

I also have envisioned another twist on this concept - using Don Piccard's Pleiaides concept. My idea would be to use the 10000 cubic foot envelope and attach 8 mylar gas cells (since there will be 8 gores on the hot air envelope) to the balloon at the equator. These attachment points will be D-rings sewn into the vertical load tapes.

I doubt that doing either of these to a friend's O-90 would be very 'legal' in the FAA's eyes. However, if you or someone you knew built a new envelope and registered it as an 'Experimental' aircraft, it would probably be easy to get it certified to use over your friend's existing basket. Talk to someone in or close to the FAA to get a better opinion since I'm not the legal type. You might also want to talk to Brian Boland as he does a LOT of experimenting in Vermont. He'd be interested in this type of stuff although I haven't told him about my ideas yet. Brian's address and phone number can be found on my website below.

suggestions will be considered...

Jon Radowski

Thanks for the ideas on the He rigs, Jon. My instructor, Charlie Manning, knows Brian Boling and I think we will take your advice about talking with him. BTW, is the volume of an O-90 90,000 or 9,000 cu ft? I thought it was the former, but your msg indicates the latter.

There's a used Roziere for sale in the Zebedee List, this might be a better bet than trying to cobble up something with an existing hot-air balloon.

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will be 8 gores on the hot air envelope) to the the vertical load tapes.

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Does anyone have any pointers to construction techniques for mylar gas cells and things of this type?