General Taskeen, on 22 February 2013 - 08:55 AM, said:
"R&D Start Date: 3041 (Federated Commonwealth), 3055 (Clan Jade Falcon)
Prototype Design and Production: 3049 (Federated Commonwealth), 3056 (Clan Steel Viper)"
Tactical Operations, page 303
The IS (more specifically, FedSuns and Lyran units) would have them at this point in the BT timeline (albeit in limited numbers), with the Clans creating their own version later (likely based on captured IS-built examples).
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MadCat02, on 22 February 2013 - 08:48 AM, said:
If you are experianced player you are probably using both double heat sink and Ferro Fibrious armor upgrades . Basicly you trading slots for dps and extra armor .
As alternative i though it could be cool if we had "Cooling System" which would have its own gauge like jumpjets and could be used to lower heat manually . That is if you want to have bigger weapons and still have efficient heating .
The specific question of Coolant Pods (along with the related question regarding the "Coolant Flush" game mechanic used in previous MechWarrior games... which the OP's proposed "Cooling System" emulates) was addressed in
Ask the Devs 18.
Quote
Q: Have you guys considered adding Coolant Pods to increase heat dissipation of a mech's heatsinks when used? [vayne]
A: Yes, we considered and then dropped the idea. We found it more of a crutch and lead to more issues than it helped with. If you're in a long, multi-targetted single player game, it makes sense. In a player vs. player environment you get a MASSIVE increase in firepower for no cost, or it wouldn't be enough to make a difference (IE. the match would never last long enough for you running out of coolant to matter, because you've already killed two people. Or, it doesn't even last a single fight, then why even have it?) Does that make sense? [Garth]
The idea has already been considered by the Devs, and has already been rejected as "a crutch" that does naught but "lead to more issues than it helped with".
There will be no coolant flush, or coolant pods, or similar systems/mechanics.