Sub combat question

@general-LD Rulebook says:
"Submersible: A submarine has the option of submerging. It can do this anytime it would otherwise make a Surprise Strike (see below). The decision is made before any dice are rolled by either side (the attacker decides first) and takes effect immediately. When a submarine submerges, it’s immediately removed from the battle board and placed back on the map. As a result, it can no longer fire or take hits in that combat. "

@s.farresque:

Hi,
I too have been searching for answers but in a simple sub vs. sub context. Manual, pg 18,“Step 2, General Combat…both attacking and defending submarines can choose to either make a Surprise Strike or Submerge…”,pg 30,“Submarines, Special Abilities, Submersible:…The decision is made before any dice are rolled by either side (the attacker decides first) and takes effect immediately.”, this is reasserted on pg 4 of the March 2009 FAQ, “Submarines Q. Exactly when is the decision made whether or not to submerge submarines? A. The decision whether to submerge submarines is made before any dice are rolled by either side in an exchange of fire , and the subs submerge immediately. The attacker decides before the defender.”. “Decides” does not equate to “attacks”.
BGG Axis and Allies Anniversary Edition, Forum, Rules, Sept, 2009, “Can a submarine ever be attacked without a destroyer present because of the ability to submerge first”. Kevin Chapman ( Patron) answers,“…so a sub can only attack another sub if the defender chooses to fight (or there is an attacking destroyer)”.
BGG (as above), in " subs vs other naval units", has other useful comments by Kevin Chapman and Don Moody on this subject.
I like the imagery of this implementation. A lone sub,or two causing isolated mayhem before sinking into the depths or just driving for their pens, until, at the slightest indication of an attack,“Dive, dive dive”. What is wrong with that…until a destroyer turns them from buccaneers of the sea into desperate survivors hoping only to escape!.
Cheers.

Was there a question in there somewhere?  You initially said you were searching for answers but never really asked any question(s).  Just trying to end your search for answers

Even a lone transport can

In AA50, enemy subs and transports can be completely ignored, as long as you don’t engage any of them.

(If you attack a sub/transport combo with a fighter and also try to land there amphibiously, the sub can sink your transport.  You can’t pick and choose what to ignore within a single zone)

It is a lot more complicated than the first glance.  I have been testing out different fleets fighting against each other, and it really seems like once fleets get big, destroyers are a major liability. 
If the enemy has a good number of subs, along with some planes or high value ships, then the you would be better off without any destroyers. 
So when is it good to have a destroyer?  If the enemy has few or no high value ships and few or no planes, then you will want the destroyer to negate the subs first strike ability. (or if the engagement is very small, like 1-4 units total, you may want it to make sure you are just outright killed).
So in other words, avoid building destroyers until you see what your enemy is building for a couple turns.  And most likely you should never build them in the pacific.

thx Kang,

@uffishbongo:

The one involving Archangel says there must be “no other Allied forces…”

This is probably a stupid question, but does that include AA guns?  I’m so used to retreating the British gun to Caucasus and now I may have knocked out 5 of my own IPC’s by doing so.   :x

That is an Allied force (a UK AAA).

This is covered in the errata thread, btw, I believe.

makes sense, thanks kreig.

@claborne:

So…. when you have a fleet of mixed subs/surface warships being attacked by only planes, you CANNOT take the subs as casualties?

No, they can not be taken as casualties.  Only if the attacker sends a destroyer with his planes can your subs be removed by air attacks.

Danke!

I like that.

The bombing runs and the damage markers give you some flexibility – still painful as all getup, but a great new addition to the SBR rules.