The actual size of the Shadowhawk 2D versus MWO's original size.
MWO's current size is currently 15 meters, just shy of what it was then.
The actual height of the Shadowhawk 2D is between 9 and 10 meters. Note that the 55 tonner also has the armor of a light mech that is barely above 4 tons, akin tot he Locust.
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Next to it, is a 60 ton modern tank.
Edit, between 2750 and 3039, Shadow Hawks barely change from the 2nd generation, though there's a third generation that grows a little bit. The 4th gen is not canonically described, but the 5th gen which starts post 3039 was made significantly larger in order to house double heatsinks, XL engine, and more armor, making it closer to normal size for 55 tonners. Though this said, here's a Wolverine.
Interesting, isn't it?
Of course, the tallest mech up until 3065 is 14.4 meters, the Executioner.
Battledroids and City Tech, both define Mechs as being "12 to 14 meters" before that got expanded...
Huh...
Hm...
Also worth noting, you can tell that the Hunchback and the Wyvern are small, because on each of these two 'Mechs, they have their ammunition stored on an externally mounted storage unit. The Hunchback's infamous 'drum' holds the HBK's ammunition. For the 4SP's only canonical art, this drum is moved from the left torso to the center torso -- which is where the ammo was moved to after fitting the second missile launcher in the left torso. Meanwhile the Wyvern's ammo is 'technically' mounted on the side torsos, the protrusion on its back spreads across the center, left and right torsos and distributes SRMs into the right torso to feed the SRM-6 and distributes LRMs through the left torso and around the engine in order to feed the center torso LRM-10. (There's also a huge emphasis on how the heat from the engine often shuts down the LRM launcher, and overriding the LRM launcher's shutdown can result in an explosion. It's also worth noting that Mechs do not override the Engine shutdown. This cannot be done. What mechs override is the weapons being disabled or 'shut down' in order to prevent damage to the weapon systems, which usually happens at 80% of 30 Mech heat if that heat is sustained for a length of time. IS pilots frequently override this in order to keep in the fight, as they usually have to ride hot or die. Clan pilots however do not normally participate in this practice.)
Another random note: Want to know the real reason this concept art is around when most concept art doesn't include 'corrections' especially on any newer mechs?
It's Alex the artist letting us know, he knew that mechs aren't as rediculously huge as some think, he tried for that, and PGI had other ideas.
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After all, Catapults are actually not much bigger than Jenners because 1) Jenners are kinda tall and 2) Stunt-leg version Catapults are around 8 to 9 meters, while their Stilt-Leg versions are between 11 and 12 meters.
Stunt-leg. Ideal for smaller urban environments, open terrain, any place with low to no cover.
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Stilt-leg. Ideal for mountainous regions, ravines, places with high cover.
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Adorable, ideal for just having some awesomesauce.
Rawr. Now that's just hot.
Sorry to edit again: But Jordan Weissman (FASA co/owner back in the hayday and Battletech creator, also the guy behind Battletech the PC game... ensured we got this version of MWO's Catapult within their art and their proportions. Notice the ladder rungs, and the pilot's size to the mech? Fits this Catapult pretty close to the "Stunt" leg design of the Catapult.)
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(And why are MWO's weapon barrels so tiny? They tried to scale some of them to the lore stated diameters. But if your mech is about 25% to 45% larger than the canon mech... the barrel will be tiny. The immense size of the Timber Wolf is why it doesn't 'run' at top speed; if it was 12.6 meters like it is supposed to be, it would have to run to achieve 81 or the lore proper 86 kph).