Hull Factor/Body Question from Rigger 3, SR3 Question on Minisubs with Depth Enhancements Options

[JaronK]

So, I've been trying to figure this out but can't seem to. When calculating the cost of stuff that includes Hull Factor in the cost for a vehicle that has a Body rating, what do you do? Specifically, I'm thinking of Minisubs getting a depth enhancement. The formula is Hull Factor X (Body or Hull Rating) X 2kg Load removed per 10 meter depth, but as far as I can tell a Minisub doesn't have a Hull Rating, and thus would have a Hull Factor of 0. But I can't imagine that's correct, because there's no reason for that Body entry to be there if things with a Body score were supposed to have no load reduction. So what am I missing here?