I'll split this topic soon (didn't realise this was in BC Scripting

)
With various degrees of possibility, either you do (from the console) an import to the module the plugin is defined (ie. import Custom.Ships.<<YourShip>>) and then do reload(Custom.Ships.<<YourShip>>) or if that fails (or if the first fails) it gets a bit trickier but this would work:
import sys
del sys.modules["Custom.Ships.<<YourShip>>"]
import Custom.Ships.YourShip
Btw, this assumes you have already fixed the problem!
And mostlikely won't work from inside QB since the (ship) menu has already been built.
But this would only be in BC:Foundation, which nobody has yet (I only have it partially

).
In the current BC it's also possible, but you would have to restart the Load plugins section, which is slightly more convoluted to do. But luckily it won't load the same module twice.
[EDIT] I should say that from a BSOD it would be rather hard to do this, I do admit that.