Re: Heating Helium?

Andreas Burkart wrote:

This was used by Picard for the Breitling Orbiter.
The principle is called, Rozière balloon, but I never read about
airships that used this.

It would seem that the Breitling Orbiter used the natural expansion of the gas at altitiude to provide the extra lift, the wikipedia article stating that the gas bag was filled to only 47% on take off.

I have found this short article relating to some Naval School thesis relating to tests on a dual enveloped airship using heating systems inside the internal envelope.

"These indicate that the simple use of airship engine exhaust heat will give more than a 30% increase in gross airship lift"

I might just have to buy this report and see if we can't get some more info on heating helium in airships.