"Terrain resistance" is a set of hidden stats in World of Tanks that impacts how mobile a tank is covering how well it "maintains" speed and traverses on various surfaces. Take this
comparison of British Tier 8 medium tanks for example - on paper the Centurion gets up to speed much faster due to its superior engine (16.7 power/weight vs 12.26), while the FV4202 can traverse faster (41.71 d/s vs 37.54 d/s). Yes, because of its resistances, the FV4202 is actually able to maintain its speed and make more of its acceleration when moving, while the Centurion by comparison will actually traverse faster.
In the real world, what determines terrain resistance of a tank? There's a few factors, and probably more than I can think of:
1) Weight - the heavier a tank is, the more likely it is to sink into the mud or break hard surfaces, drastically increasing the resistance it encounters
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| You ever get that feeling like you're slowly getting shorter...? |
2) Suspension - the more robust and responsive the suspension, the better it ran. It's why the Christie was such a game changer in early tanks, and why the HVSS of the "Easy 8" Shermans was considered an improvement over the VVSS of earlier versions.
3) Track width - wide tracks allow more contact with the ground, which in turn allows more control and helps better distribute the weight of the tank. With the Shermans, HVSS tanks were able to equip wider tracks, allowing them more manoeuvrability than previous models.
4) Track and suspension design - this is a strange one really; a track is a just a strip of metal right? Well, not exactly. Tank tracks are surprisingly complex construction of, amongst other things, different metals, assorted pins, and rubber. Some designs proved more effective than others both in performance and ease of maintenance - take the ubiquitous T-34 for instance. Where other designers went to great lengths to create locking pins and alignment systems for their tanks, the Soviet designers simply used a small piece of metal welded to the side of the tank to whack pins back into place after each rotation. Such design variations meant that tanks like the Shermans had a tendency to bog down in mud, while overly-complex suspensions like the Panther would become caked in dirt and debris, slowing the tank down over time.
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| You want me to change WHICH wheel now?! |
5) Undercarriage clearance - ever see a low-slung sports car try to get over a speed hump? Same principal.
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| Damnit Phil, I told you not to drop the damn suspension! |
So how does this translate into World of Tanks?
At the moment, WG use resistances as a "soft stat" - something they can tweak with relative impunity to buff or nerf a tank's mobility, without actually impacting on the "hard stats" of horsepower, speed, and overall traverse (figures that are "official" and cannot be easily changed, especially for production tanks). After all, who
really knows if the T-54 handed mud better than the Cromwell? After all a tank's reputation for mobility is often subjective or based on hard land performance, not on mud or snow.
Is this the right way to go about it? Personally, I'm not certain it's the best method. A tank's ability to traverse on assorted terrain should, in theory, be a measurable by simply taking it to a muddy field and going for a spin. Unfortunately, there are a multitude of reasons as to why this is not done ranging from a lack of tanks and muddy fields of similar consistencies to test with, to the fact that Wargaming do need some "hidden" metrics they can tweak to keep tanks competitive relative to others.
But that's just my 2 cents.
