[Taqwus]

The easiest way is to not build that many ships. No, seriously -- you generally don't need *that* many ships, especially warships (and it's warships that worry most about obsolescence). In the early game, you don't *want* that many non-colony ships, because the maintenance cost (unless they're mothballed) can cripple your ability to build facilities, which will in turn prevent your production base from growing rapidly. You can fall from 1st to 9th by having too many pop transports and scout escorts.

Another is to note that you don't need to upgrade your designs *that* often, either. If you have CSM-II frigates, you may not need to upgrade to CSM-III unless the extra squares of range are vital (e.g. opponents got there first); maybe you can wait for another level, or even until you can build destroyers.

Beyond that, a useful, logical (to you) naming scheme helps. I've named ship classes like CR-CS-1 for [Colonizer, Rock] - [Colony Ship hull] - [First Generation], CR-CS-SP-1 (first solar powered colonizer -- useful when using the Minister, which doesn't seem to understand the notion of supply), PD-BC-2 for second-generation point-defense battlecruiser, BA-BC-1 for first-generation beam-attack battlecruiser and so forth.

You can then sort by name in the ship viewer, and check whether you've got unduly obsolete vessels.



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-- The thing that goes bump in the night