Well, I don't really bother myself with the realistic attributes of things. Besides, it's sci-fi, so who cares if things are feasible.

Anyway, if you've ever played Halo, think of the plasma grenade explosion. My fusion fire is about the size of half the engine, and a deep blue/purple. It looks like a tall fire on a stove except skinny. I can make a mess-pic of it for you, if you want.

-Speaker for the Dead