Why not a live aboard blimp?

[tid]

2 words: sky crime

[crypto]

As a long term solution, no.

Helium diffuses through the gas envelope and needs to be replenished. So, unless you have a way to resupply that, you're boned.

[doitnstyle1]

1)Easy known target. Just wait until you come down and attack.

2)You are still susceptible to high winds at lower altitudes that can crash a blimp.

3)There is a helium shortage and is hard to find for non commercial applications. Hydrogen can be developed through electrolysis as a viable alternative but then you run into
http://upload.wikimedia.org/wikipedia/c ... urning.jpg

4) The lift ratio for a protective underbelly to inhabit would be cost prohibitive.

5) Even if you tether to the ground, your tether is a weak point that can fail, or provide access to a wily individual.

[crypto]

[majorhavoc]

So in comparison, my nuclear amphibian battleship bugout plan is starting to look p-r-e-t-t-y good about now.

[crypto]

Yeah, you'd have better luck door-gunning on a submarine.

[crypto]

3)There is a helium shortage and is hard to find for non commercial applications.

There isn't really a helium shortage. Helium is one of the more plentiful gasses on earth The problem is that the government is still selling through its strategic helium stockpile at cut-rate prices and so the market isn't willing to invest in helium production that would have to sell at 2x the surplus rate to break even.

[Squidi]

Mutant Kangaroos agree with your plan.

[CitizenZ]

I'm on board.

[Benbrutal]

Crewed a PTDS aerostat (what you call a tethered LTA with no engines) 4 years in Baghdad. Pressure inside is about 3 PSI (yes three), I have brought one down after a month in the air with 20 bullet holes in it. Main problem is heat raising the pressure too high which causes it to burp out helium. 1000 cubic feet of Helium provides 66 pounds of lift at sea level, so you need a lot, we had 74,000 cubic foot aerostats in Iraq and the Stan to carry the payloads.

[Mad Mike]

Crewed a PTDS aerostat (what you call a tethered LTA with no engines) 4 years in Baghdad. Pressure inside is about 3 PSI (yes three), I have brought one down after a month in the air with 20 bullet holes in it. Main problem is heat raising the pressure too high which causes it to burp out helium. 1000 cubic feet of Helium provides 66 pounds of lift at sea level, so you need a lot, we had 74,000 cubic foot aerostats in Iraq and the Stan to carry the payloads.

The slow leakage rate caused by low pressure was the driving force in developing incendiary cartridges during WW 1. Those were quite effective against hydrogen filled balloons. Brought them down in a big hurry!

[TacAir]

The Mars aerobot effort

After the success of the Venus VEGA balloons, Blamont focused on a more ambitious balloon mission to Mars, to be carried on a Soviet space probe.

The atmospheric pressure on Mars is about 150 times less than that of Earth. In such a thin atmosphere, a balloon with a volume of 5,000 to 10,000 cubic meters (178,500 to 357,000 cubic feet) could carry a payload of 20 kilograms (44 pounds), while a balloon with a volume of 100,000 cubic meters (3,600,000 cubic feet) could carry 200 kilograms (440 pounds).

The French had already conducted extensive experiments with solar Montgolfieres, performing over 30 flights from the late 1970s into the early 1990s. The Montgolfieres flew at an altitude of 35 kilometers, where the atmosphere was as thin and cold as it would be on Mars, and one spent 69 days aloft, circling the Earth twice.

Early concepts for the Mars balloon featured a "dual balloon" system, with a sealed hydrogen or helium-filled balloon tethered to a solar Montgolfiere. The light-gas balloon was designed to keep the Montgolfiere off the ground at night. During the day, the Sun would heat up the Montgolfiere, causing the balloon assembly to rise.

Eventually, the group decided on a cylindrical sealed helium balloon made of aluminized PET film, and with a volume of 5,500 cubic meters (196,000 cubic feet). The balloon would rise when heated during the day and sink as it cooled at night.

Total mass of the balloon assembly was 65 kilograms (143 pounds), with a 15 kilogram (33 pound) gondola and a 13.5 kilogram (30 pound) instrumented guiderope. The balloon was expected to operate for ten days. Unfortunately, although considerable development work was performed on the balloon and its subsystems, Russian financial difficulties pushed the Mars probe out from 1992, then to 1994, and then to 1996. The Mars balloon was dropped from the project due to cost.




NASA long endurance balloon/airship


self inflating hot air balloon


http://courses.ae.utexas.edu/ase463q/de ... idterm.htm more at link.



German balloon for Mars



DIY solar balloon....

all kinds of fun balloons on the web, just no floating RVs.