Hades is possibly going after FS-classifications with his remark (where bombers don't have
that heavy turrets, nor are that large) - but seeing that it is based on Wing Commander, "bomber" should still be the correct description (as long as you don't import it into the FS-timeline, that is).
Oh and the Longbow still was a bomber in WC4 - it didn't cease to be at the end of WC3

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About the model itself - hmm, I'm not quite as enthusiastic with this as with most of your other models, but still it looks well, and the idea seems interesting

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From it's looks, it somehow reminds of the bow of a WC1 Venture Slanted onto an enlargened Longbow rear-section... Nothing bad about that, but the whole thing is just a bit
too boxy for my perception...
Compared to the drawing, I'd also say there should be an additional intake at the top after about one third of the length - where you have some tubes going around the edge of the broadening cross-section.