Picture I http://kimmontaidearvioita.blogspot.com/p/the-havoc-plan-of-nasa.html Kimmo Huosionmaa When we are thinking about the floating city in the atmosphere of some planets, we might think that this structure would need very much fuel or nuclear propulsion for floating above the clouds. That would not be necessarily true, even this city or giant spacecraft would stay in the atmosphere of some hostile planet. Of course, the nuclear power and the turbines would keep the heavier than air-structure above the planet Venus, and the "heavier than air"-solution makes those systems very weird, but this kind of structure is safer than airships, but there is one problem. Staying in the atmosphere that system needs machine power and this kind of structures is no experiences before this program. The HAVOC (High Altitude Venus Operational Concept) could be heavier than air because this structure is not so sensitive for the winds, and that could make the thing safer, but th...