Gryphos
Auror
Very early on in the world-building process of my story I decided that airships would be a very prominent aspect of my world. The 'Aerial Revolution', well, revolutionised how the world worked, with fast and reliable transportation across any terrain and a new dimension in which to wage war.
When I originally decided to have airships I also decided that they were going to be very different from real life zeppelins. I wanted them to be smaller and have the gondola be suspended beneath the balloon, and the ship be propelled and steered by propellers.
Basically, I wanted my airships to be like this:
Only recently have I been forced to really come up with the details of how airships operate, and consider all kinds of crazy things.
So, with the balloon so small in proportion to the hull compared to real life, I decided that I wasn't going to use any real world gas as the lifting agent. So I made up a gas which for the time being I'm calling aerithium. Aerithium is a non-combustible gas with tremendous amounts of lift, allowing the balloons to be a lot smaller. The balloons would also be compartmented so if there's a hole the entire ship won't go down.
So that's how the ship stays up, sounds good. But how does it come back down again? Well, I thought that, so long as the lift of the gas and the weight of the ship's load are in equilibrium, the ship could be made to rise and fall through use of vertical mounted propellers on the sides of the ship. Meanwhile horizontal mounted propellers on the stern move the ship horizontally. (Yes, I know how zeppelins corrected altitude in real life, with air intake and whatnot, but because of the reduced size of my airship balloons, that won't work here)
But then I realised, for that to work the ship's load weight must be kept constant, but with passengers boarding and leaving and cargo being loaded and unloaded, the weight's going to be changing a lot. So perhaps then it's possible for the crew to alter the amount of gas in the balloon. Letting gas loose to account for loss of weight would be simple enough, but what about when you're gaining weight? There would definitely be pumping stations at docks, but when not docked I'm not entirely sure what they'd do. One option is to just jettison stuff of equal weight to what you've gained, but that might not always be possible.
So I had another idea, something I'm calling aerithium bricks. On ships they would have stores of aerithium bricks which, when burned inside a special compartment, will break down into aerithium and fill the balloon. The brick doesn't need to be pure solid aerithium or anything like that, probably just some kind of compound. But even so, I don't know a huge amount about physics, so it's possible that might not be a sound idea.
So what have I missed? What have I failed to consider? Also, how equal must the lift and weight be in order for the propellers to be able to control altitude? Will it need to come down to a single kilogram or is there a bit of leeway?
When I originally decided to have airships I also decided that they were going to be very different from real life zeppelins. I wanted them to be smaller and have the gondola be suspended beneath the balloon, and the ship be propelled and steered by propellers.
Basically, I wanted my airships to be like this:
Only recently have I been forced to really come up with the details of how airships operate, and consider all kinds of crazy things.
So, with the balloon so small in proportion to the hull compared to real life, I decided that I wasn't going to use any real world gas as the lifting agent. So I made up a gas which for the time being I'm calling aerithium. Aerithium is a non-combustible gas with tremendous amounts of lift, allowing the balloons to be a lot smaller. The balloons would also be compartmented so if there's a hole the entire ship won't go down.
So that's how the ship stays up, sounds good. But how does it come back down again? Well, I thought that, so long as the lift of the gas and the weight of the ship's load are in equilibrium, the ship could be made to rise and fall through use of vertical mounted propellers on the sides of the ship. Meanwhile horizontal mounted propellers on the stern move the ship horizontally. (Yes, I know how zeppelins corrected altitude in real life, with air intake and whatnot, but because of the reduced size of my airship balloons, that won't work here)
But then I realised, for that to work the ship's load weight must be kept constant, but with passengers boarding and leaving and cargo being loaded and unloaded, the weight's going to be changing a lot. So perhaps then it's possible for the crew to alter the amount of gas in the balloon. Letting gas loose to account for loss of weight would be simple enough, but what about when you're gaining weight? There would definitely be pumping stations at docks, but when not docked I'm not entirely sure what they'd do. One option is to just jettison stuff of equal weight to what you've gained, but that might not always be possible.
So I had another idea, something I'm calling aerithium bricks. On ships they would have stores of aerithium bricks which, when burned inside a special compartment, will break down into aerithium and fill the balloon. The brick doesn't need to be pure solid aerithium or anything like that, probably just some kind of compound. But even so, I don't know a huge amount about physics, so it's possible that might not be a sound idea.
So what have I missed? What have I failed to consider? Also, how equal must the lift and weight be in order for the propellers to be able to control altitude? Will it need to come down to a single kilogram or is there a bit of leeway?