Why are you creating a copypasta duplicate of your previous thread?
http://forums.startrekonline.com/sho...d.php?t=266107
Relevant answers were given there. Anyway:
1. When you die or drop aggro in missions, i believe NPCs reset to full health. My gaming com is down this week, so i cannot reverify that.
2. Apart from Undine ships with extremely strong regenerative powers; most, if not all NPC ships have science/engineering abilities that they use to heal themselves.
3. If you're talking about NPCs passively regenerating in combat, remember that your own crew and power grid can maintain your ship and shields in combat. Likewise, NPCs also have crew complements that will affect their repair rates.
All these are not bugs and are part of basic game mechanics. However, if you encounter some event where this regeneration is excessive, do state WHAT mission that is so others can test it, or for cryptic to look into rebalancing.
I am fairly certain that you have misnamed your thread title, as it says that enemies are respawning, not just repairing(fast?). Barring certain mission scripts that might have this feature, and i can't think of any offhand, ships do not normally respawn for a very long time, like if you go afk for 30 minutes between groups within a mission.
Do try to do some basic spellchecking before posting, as many people tend to ignore and/or troll poorly worded posts. I'm usually one of the latter, but am feeling abnormally... generous this morning.