Of course, if you do, the ship will get a lot lighter every time you make a turn and the water sloshes over the side.

You can draw anything you want, but that doesn’t mean you can ever build it.

A small blimp can easily cost 2 million dollars and even at 4 million, the size of the airship would not justify anything more than a semirigid design. The military still funds R&D into composite rigid airships but in general, airships are too large, too slow, and too easily damaged for military use.

Ultimately, there are very few markets for airships due to public perception. The current Zeppelin NT is scrambling for buyers with the concept of a rescue platform (hospital airship) being the latest proposal.

Somehow the cost of entry into the airship business must be lowered and markets identified. I suspect that the most likely market will be for remotely controlled UAV high altitude communication platforms as the most likely to be profitable (small blimps, solar powered and cheaper than satellites).

Recreational use as a ocean liner style cruise ship also has a limited market and current ocean liners carry at least 1,000 passengers before realizing a profit. An airship will likely carry between 50 and 100 passengers. I don’t think passengers are going to pay 10 times the cost of an ocean cruise to just be in the air rather than on the water.

Personal RV’s captures a lot of imagination as it would bring a sense of personal freedom but sailing ships large enough to live on typically start at $200,000 and go up to $2,000,000. Any personal RV airship will have to be in that range and currently only small blimps with a cramped gondola for a handful of passengers are in the top end of that range.

Also, hydrogen is a lot safer than the public realize, even with the Hidenburg, the hydrogen would’ve burned in a controlled fashion since it has to mix with air before it’s combustible (It was the flammable skin that started and kept the fire going) and the hydrogen were in 17 separate gas bags. Besides, what if it was mixed with FM-200 or some other Halon like fire suppressant. Keep in mind that all these “fire suppressants” are actually in the Propane family (FM-200 is HeptaFlouroPropane). Hydrogen can also be used in fuel cells as a backup power source especially since some gas must be removed as the airship gains altitude anyway, the limit at which no more gas can be removed due to the airship design (volume of balloonets in blimps) is known as pressure altitude.

The advantage of vacuum over helium is not infinite but rather equal to the density of the helium which is about 0.18 g/L. Therefore for every cubic metre, a vacuum could lift 180 grams more than helium could, even nanotechnology would have a hard time making a vacuum container that light. With a cubic metre of helium lifting 1.072 kg and a cubic metre of vacuum lifting 1.252 kg, the advantage of vacuum over helium is 16.8% not infinity The infinite bit is from the same flawed logic that have the general public assuming that people would explode in the vacuum of space when in reality we withstand 1 atmosphere of differential pressure quite easily. Essentially, a gas is already an efficient a vacuum lift cell based on nanotechnology as each molecule of gas keeps a certain volume free of anything else, would heavier carbon bucky balls do any better when carbon itself is heavier than helium or hydrogen? The volume occupied by each molar of gas is much larger than the conceivable volume of even large bucky balls. Also how much are you willing to pay for that additional 180 grams per cubic metre.

I would love to see airships return but first there has to be a market, a better way to build them and the return of hydrogen as the mandate for helium use is unreasonable and only brought about by public fear and ignorance.