Pre-existing damage to convoy?

[Nyarlathotep]

Radio report lead me to a large convoy off the coast of Spain. When I closed to attack, I noticed that one of the DD's and a small merchant were both already on fire. This proved very helpful, in that I set up my attack by sneaking past the damaged escort. Plus, what luck, apparently his depth charge rack was damaged because he was only able to fire the sideways-launching ones. This allowed me to run directly underneath him on an attack run, make a quick turn and go deep to break contact.

So do spawned ships have a chance of being damaged in GWX, or do I owe some luftwaffe pilot a Beck's? I figure they *might* have been in range of a base somewhere..