Editing The Empire (Warhammer Fantasy) (section)

===And 'Heavily Armored Steam-Powered Cavalry'===
The Empire's [[Steam Tank|Steam Tanks]] however are, perhaps unsurprisingly, the most unrealistic part of their army, even then they are somewhat plausible. The problem with steam as a method of propelling a vehicle is that it's relatively inefficient as a propellant despite what steampunk enthusiasts tell you. The issue is that to turn coal into power, first you need to burn the fuel in order to heat the metal holding the water over the fire (the pan as it were), then heat the water to 100+ degrees Celsius to boil it, then have the steam travel a set of pipes to the pistons, then you need to work the pistons, and then you need to turn the wheels or propeller, all the while you're losing energy due to thermodynamics at each step, plus as compared to petrol, coal and wood have less energy per pound. Trains and ships can get away with using coal and wood power because, like a quadratic wizard, they pass a point where they became so big they become able to lug enough water and fuel (either coal, wood or oil though the Empire most likely uses wood given how heavily forested the Empire is) to power themselves for long distances, and as you go farther along you become lighter since you're burning fuel as you go. Steam power may be relatively inefficient, it's also relatively simple since they're mostly plumbing to put together, to scale up to a level that gas engines can't do nearly as well. So getting something as small as a tank to carry enough fuel and water for any length of a fight, along with all the powder, weapons, ammo and armor is a very tall order. [[Warmachine]], as a point to compare, tells us that a warjack can operate for only 30 minutes to an hour. The Empire's Steam Tank is doubly handicapped by the fact that not only it does not use black powder, but shoots its cannon with compressed steam, which would further chop down the likely running time of the engine. That said, the Steam Tank is not completely unrealistic. As mentioned, the Empire is very heavily forested with plenty of rivers and small bodies of water. While they may only be able to run their tanks for less then an hour, refueling would be a simple procedure of chopping some trees down and pouring a few buckets of water in the internal tanks. The lore has the inventor dying while testing alcohol-fueled aircraft so this might have some relation to the tanks. Of course, the Empire also has magic so they could just point a bright wizard in front of the boiler and tell him to go nuts, so in truth it's not the steam engine that is the biggest problem with the steam tank.

The biggest issue with the Empire's Steam Tanks, aside from the steam powered gun, is the horrible design. Forget about the jokes about the [[Leman Russ Battle Tank]] being a poor design for looking like a [[World War I]] tank, the Steam Tank's four wheels would make the thing sink into any ground that was not paved unless it was dense soil or other such stable features instead of loose dirt or sand or soft clay (or, God forbid, mud), and the rickety wooden axles would likely snap at any speed over rough ground and replacing it with metal has its own weight and engineering issues, and it's likely they use a steam cannon since a proper gun would shatter them if fired (the steam cannon’s description seems to imply it’s like a fire hose that shoots scalding vapor). Aside from the Steam Tank's sheer complexity, its shitty design is likely the only thing keeping the Empire from forming its own Panzer divisions. Although, there may also be alchemical or magical aspects. Since when the guy that built them died the Empire didn’t understand the designs. Even so, at least the Leman Russ has the excuse that it was just an STC tractor someone slapped guns on. The steam tanks of Fantasy were designed to be mobile weapons platforms.