The way I test ships is..
In my plugin I set up two governments, "Blue Team" and "Gold Team" (from the DD-21 competition) which are mutual enemies. For each govt, I made a dude resource for the lightning, the rapier, the hawk, and the corvette. I set up a mission "Blue Lightning" which cause 1 lightning of the Blue team to appear in system with me. I set up other missions-- "Gold Rapier", "Blue Hawk", etc. which work similarly.
To see a rapier-lightning fight, I accept the missions Blue Lightning, and Gold Rapier, and leave the planet. I then see Blue Team's Lightning fighter destroy a Gold Team Rapier fighter with 4 missiles.
PlanetPhil probably has better way...
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