(When playing as TEC rebels, you have them at T3 asteroid planet slot)
The corsair has 3 weapon types, missile weapon has the longest range, I think it should be possible to fire them on the move and close in to fire the light and medium guns as well.
If engaging targets that do not come closer to the pirate heavy cruiser, the ship fires only missiles. With upgrades to range increase, automatic targeting can make it less likely the ships do get to use their full arsenal.
It is not a solution to level the ranges, because missiles do get a 12% research bonus, while guns do not, still resulting in a mismatch.
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Another issue
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also pirate ships, (maybe others as well) when told to move, seem to not be able to fire their weapons, while if they chase something on their own, they do fire.
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Akkan could get rid of broadside, possibly all its 'many' guns can fire forward.
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when in difficult terrain, ships do not exactly face the enemy in 3D space, resulting in big disadvantage. One ship faces enemy, the other is above or below, but does not bother to align itself completely.