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)
So cosmic radiation destroys metal as well? Then why haven't the Mars rovers turned to dust? And what about further out probes, such as voyager, which have been in space for decades and are still working? And if airships are so susceptible to damage by radiation, why aren't digging machines, spacesuits, etc? Then, think of other ways of transporting cargo across the surface. Trains need tracks, which are impractical for an autonomous colony to produce. Rovers or trucks need to navigate rough terrain. Balloons are at the mercy of the wind. Ships, well, those are out of the question, unless Mars is Terraformed. It is really a toss-up between heavier then air aircraft and airships. I think the idea of an aircraft like the C-5 is kind of cool. I met a guy who flew C-5s at an airshow, and he jokingly said the the plane was from Mars. T.Neo 09:57, 8 August 2008 (UTC)
- The destruction of metals by radiation is a slow process. The existing rovers are built for a limited lifetime. You can find some information about the effect of radiation on metals and other materials on the internet:
- I am sorry for the facts, but we have to face it. I am sure we can build a Martian colony, but we must be very careful with every aspect of our ideas. On Mars the resources are rare, especially energy. That's why the wear lifespan of every product must be much longer than on Earth. The Martian settlers will not be able to afford big things with a limited lifetime. The long term stability of a colony depends on how effective they can work with the given resources. Probably, the settlers will develop their own technology after a while, adapted to their planet, with new ideas we can not even dream of. For now, we can only define a solid base to give them a start. How about a railroad? -- Rfc 16:27, 8 August 2008 (UTC)
A railroad sounds like a nice idea, because it is pretty low tech, has a good wear lifespan, etc. So, say, if you wanted to build a railroad from Pavonis mons to Ascreus mons. You have to lay the tracks. There are rocks in the way. These will have to be moved. There will be ravines and sinkholes. These will have to be bridged. There will be uneven ground. etc, etc, etc. Then, think of the energy required to make the tracks, sleepers, etc. Metal is the preffered material, lets say, iron or steel. This has to be mined, the ore proccessed, smelted, etc. This is a very energy hungry process. Then we have the train. the train is the easy bit. It can be simple and low tech, and can run on some sort of energy storage. The problem is the energy expenditure for the entire project. Factor in other things that fatigue materials, corrosion, metal fatigue, etc. Radiation is first and foremost a health risk, which is why the colony will be underground, in a cave, covered in regolith, etc. Short range distances will be traversed by pressurized rovers. "Roads" can be created by moving rocks and placing rocks as markers. I doubt machines on Mars will have a wear lifespan of more then 15-20 years. Some components can be replaced. Hopefully there will be some recycling possible. A railroad will require too much energy in the short term. The only flying technology that is at an advantage on Mars is rockets, due to the lower gravity. How practical it will be to build such rockets remains to be seen. T.Neo 11:52, 9 August 2008 (UTC)
- Yes, there are no easy transport systems to be built on Mars. Even a railroad is expensive, your list of problems is formidable! At the beginning I do not see a use case for long distance journeys. The settlement will be placed where the resources are. Only short distances must be managed, e.g. the way of a repair team for the solar panels. I would like to leave the long distance journeys for the next generation. -- Rfc 19:56, 12 August 2008 (UTC)
The problem with rovers is that large rocks may lie in the way. Move the rocks to the side of the road so you can use them as markers, and you have suddenly killed two birds with one stone (Almost literally). It seems air transport is heavily disadvantaged on Mars due to the thinner air. But I know that there are high altitude balloons that go to the edge of space, where the air is at a similar pressure to that on Mars. I know that these balloons were pretty big. Mars is abundant with iron oxide dust. Is there a way to create iron out of this oxide using minimal energy? For critical components of systems maybe steel could be created, since there is carbon available in CO2. A railroad does have some advantages, if it is built correctly it might last centuries, even millenia, if iron does not rust and corrode like it does here on Earth. I would still like to see lo-tech simple space access for colonists. If that can happen, then we are set for living on Mars. T.Neo 07:02, 13 August 2008 (UTC)
