The following link might be of help:
This may seem like a simple question,but i have not seen it addressed anywhere. Can a player retreat before any round of combat occurs,basicly skipping steps 1 thru 4 and going directly to step 5 in the combat sequence? I have a friend who,after seeing his other battles go down so so, wants to forgo or retreat his last battle with out conducting any round of attack. Incidently we are playing AAA50, but would like to know if this is the same for all versions.Please help Kreig you are the only one he will listen to!
Retreating is done at the end of a combat round. You can’t skip the prior steps and go straight to retreating, so you must fight at least one round of each declared battle. It’s the same in all versions.
However, in AA42, AA50, and AA40, attacking (and defending) subs may avoid fighting by submerging at the beginning of the first round if there are no opposing destroyers.