So I have accumulated six of those tripple rocket launchers and wanted to use them against fallen ship part. Here is how it was:
My setup. Launchers are ready to fire:

One early shot from trigger-happy dude. One scyther down already:

First wave of explosions. Most scythers down:

Second wave and third wave. Ship part destroyed, some bodies annihilated and see how that centipede lost his weapon:


Finishing up with charge rifles. I have two injured colonists, but nothing too bad:
My setup. Launchers are ready to fire:

One early shot from trigger-happy dude. One scyther down already:

First wave of explosions. Most scythers down:

Second wave and third wave. Ship part destroyed, some bodies annihilated and see how that centipede lost his weapon:


Finishing up with charge rifles. I have two injured colonists, but nothing too bad: