I do not know if this is a new technique, or one that has been tried and rejected, but here it is.
Although Milkshape can not make a true break model, one that breaks a ship up into several objects when it explodes, you can make a model of one single piece of the ship that will fly out of the explosion.
The examples below are rough tests that I made of this technique. I created the break models by simply importing the orignal into Milkshape, deleting some of the groups, and exporting it as the break model.
Before I used them in-game I would improve the break models by making sure that there were no missing polys, replacing the textures with textures showing damage, and replacing groups with new "damaged" groups rather than just deleting them.
I am sure that there are more ways that the Milkshape experts can come up with to improve them.
I am not saying that these replace true break models, and I would never use them on a model for public release, but for the person modeling for their own game, who only has Milkshape, it is better that nothing.
Screenshots: