Talk:Airship

Airships- disadvantages

• The stronger radiation destroys the hull. - If you mean UV radiation, this is true. Aren't there UV resistant plastics out there? Can they be made on Mars?

• Due to the thin atmosphere the airship must be several times the size, reducing the efficiency heavily. - My thinking is that the lower pressure would mean that there would need to be less hydrogen. Maybe there is something counterintuitive about lifting gases that I do not know about.

• The large surface of the airship results in strong forces during dust storms. - this is one of the problems I have encountered. If you see airships on Earth, they are tied down to a mast so that the wind can blow any which way, and the airship "weathervanes", and thus does not present such a large cross-section to the wind. Another alternative could be to build a very large hanger to store the airship in. However, building such a hanger would be a mammoth task. The airship would not be flown if there were large dust storms at the time. T.Neo 12:34, 7 August 2008 (UTC)

Hi T.Neo, there is not only UV, but also hard cosmic radiation and solar wind, destroying even metallic materials after a certain period of time. I do not know exactly, how long it takes to brittle a 1 mm aluminium hull under Martian conditions. I'm afraid there isn't any material stable enough for this purpose for a reasonable period of time.

The lifting of an airship works with an equilibrium of its own mass and the mass of the atmospheric gases it displaces. The thinner the atmosphere the larger the volume to displace. In contrast to a simple balloon an airship needs a propulsion system and fuel to carry, which increases its own mass. Say, the airship's weight is 1000 kg (which resembles a mid-size car). Now, this airship must displace a volume of atmospheric gases, which has the same weight. You may calculate this, but I guess it is a huge volume. Because of the low pressure the volume is more than a hundred times bigger than the equivalent in the terrestrial atmosphere. The huge volume means a huge hull, which must be part of the 1000 kg. The result: Compared with Earth a Martian Airship with the same mass must be a hundred times bigger.

The idea of balloons and airships is still worth to think about, and we are going to find out which transport mechanisms are feasible on Mars and which are not.

-- Rfc 20:39, 7 August 2008 (UTC)