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When you are near the jump hole to New Berlin, a derelict will show up on your map:

Old Imperial Navy Fighter (C5) - 2xDIAMONDBACK, Wasp launcher, 10xWasp missiles, 20xDrone Mine, 20xCountermeasure Flare

There are more of these here in Sigma-13, but they'll have to wait until you're done with the story.

When you get to New Berlin, sell your Cardamine and buy Light Arms.

At Bruchsal, sell the Light Arms and buy H-Fuel. Also buy six Luger Type A guns, and a turret if you can; they have the best damage/second of any Class 6 gun. Try reading the news in the bar to see the Rheinland spin on recent events.

You only need to destroy one of the experimental ships; just fly to a spot where it's between you and the other ships, and fire away.