Patent ID: 9568918
Date: 2017-02-14
CPC Classifications: B64B,G05D

Claim:
1. A balloon comprising: a. a flexible volume balloon hull configured to contain a lifting gas, wherein said flexible volume balloon hull has a maximum volume (V b. a flexible volume ballonet contained within said balloon hull configured to contain a refrigerant gas; c. a refrigerant gas transfer device in fluid communication with said ballonet and comprising a radiator/condenser for cooling said refrigerant gas and a radiator/evaporator for heating said refrigerant gas; d. a first valve positioned between said ballonet and said radiator/condenser to allow for removal of refrigerant gas from said ballonet; e. a second valve positioned between said ballonet and said radiator/evaporator to allow for introduction of refrigerant gas to said ballonet,