I found this post in another thread of AA50, in which Defenseless Transport and DDs blocking all Subs was introduced:
I will try to make some spaces for easier reading.
Kavik Kang was amongst the first to suggest the 1 DD :1 Sub ratio but for movement blocker only.
This example show how to use so called Fleet Submarines tactics to maximized their potential as sea-fodder units.
I’ve been learning AA50 by playing it and trying out different openings offline and watching other people play and what they do. One thing I’ve noticed in watching other people play is that almost nobody, even the very best players, seems to understand the ramifications of how subs work within the new AA50 rules. I’m an old man for a gamer and I’ve been playing games for over 30 years. My favorite games have always been naval combat games, and AA50’s new sub rules are based on how subs work in certain other, more complex games. So I already have a lot of experience with the concept, and a pretty good understanding of naval combat. So I thought I would provide this little primer on subs and naval combat within AA50 in the hopes that Japanese players will stop sailing within range of my well composed US fleet thinking that they are safe just because they have 1 more carrier than I do and then dying to the AA50 version of a carrier air strike.
First, the main sub users in AA50 are USA and Japan. England generally has little use for subs, other than maybe for a single attack on the Italian navy. Italy might build some fleet subs as cannon fodder in their fleet, but without carriers have no real need for subs. Japan also only has a need for fleet subs (which I will explain later), but has much more of a need for them than Italy does because they have carriers. Once you truly understand how subs work in AA50, you’ll understand why they are such an essential part of any fleet.
Subs are defensive units and they are the infantry of the sea. The most important thing to keep in mind about subs is that, if a destroyer is present, they can’t safely move within range of enemy units. One destroyer and as many planes that can reach will get to take one round of shots at your subs (more rounds if the destroyer survives the first round) and they will attack your subs, which only defend at a 1. You can’t move within range of enemy destroyers or you will die. But if your subs are supported by air units the enemy fleet can’t move within range of your subs, either. That last point is the crux of the issue.
The point most seem to be missing is that subs are meant to die. It doesn’t matter that they only attack at a 2, subs are defensive attacking units.
The best example are what I call fleet subs within AA50.
Fleet subs are subs that travel with a carrier fleet. Their sole purpose is to die in an air strike on an enemy fleet.
In the real world carrier planes fly out great distances to hit enemy fleets, they don’t sail up and get into a close range fight with them. This is actually how carriers work in AA, as well, except that the carrier planes need to be escorted by subs. The subs are only there to die, and you would ideally have as many subs as hits you believe you will take in one round of combat with the enemy fleet (against the IJN, this means 4- 6 subs). This has a huge impact on the stand-off between two fleets such as the US and Japanese fleets in the Pacific.
Let’s look at a typical stand-off between two typical carrier fleets and what happens to one of them if it allows an air strike supported by subs from the opposing fleet.
Let’s say that the Japanese fleet is, as usual, more powerful than the US fleet. The Japanese fleet is more powerful, so the Japanese player moves within 2 spaces range of the US fleet at Hawaii believing that he is safe. The Japanese fleet consists of 3 carriers (with 6 fighters), 1 battleship, 1 cruiser, and 1 destroyer. The US fleet consists of 2 carriers (with 4 fighters), 2 destroyers, and 4 subs. The US fleet performs an air strike with 4 subs, 2 destroyers (using them because he didn’t have enough subs to send in this instance, and 4 fighters. The carriers stay in Hawaii. The battle calculator will tell you that we will lose this fight badly, but the battle calculator isn’t taking everything into account AND assumes that we will stay for multiple rounds of combat. We won’t be. We are the attacker and we can retreat whenever we want. In this particular example they will almost certainly have to take one shot and leave because all the subs will die in round 1.
So we shoot and get 4 hits (average), 1 sub and 3 other hits.
The Japanese player takes the free hit on the battleship from the sub, loses the destroyer and then must chose between a plane, cruiser, carrier, or battleship for the other 2 hits.
He probably kills 2 planes.
The Japanese fleet shoots back and gets 6 hits (1 better than average) the US kills the 4 subs and destroyers and then retreats all 4 of his planes from the battle (if a DD lived retreat it as a blocker). The US fleet in Hawaii is 2 carriers with 4 fighters.
The remains of the Japanese fleet are 3 carriers, 4 fighters, 1 battleship, and 1 cruiser.
The US mostly lost only subs which contribute very little defensively too the fleet other than dying instead of better units, the Japanese lost fighters, the primary defense of the fleet.
They have to withdraw and rebuild expensive fighters.
The US just needs a couple more subs and destroyers which if they are in a stand off with the Japanese navy are probably already arriving from the west coast at the end of this turn allowing the US fleet to remain in Hawaii. We lost 2 more units (we lost 4-6) than the Japanese navy did, but due to the nature of the combination of subs and airplanes attacking, in the grand scheme of things, we clearly won the fight. Had the Japanese player had subs and destroyers protecting his planes and larger ships all we would have done was whittle down each others sub/destroyer forces a little. The US fleet in this instance had a superior composition with its combination of subs and fighters so the larger Japanese fleet comes out on the short end of the stick. This is actually even worse for the IJN because the US would actually also have 2 heavy bombers attacking from Hawaii that I intentionally left out to show just the matchup between the fleets alone.
The key factor is the effect that and air strike has in relation to the defensive strength of the fleet. If you trade subs for fighters with an enemy fleet, when the battle is over your fleet is stronger defensively than the opposing fleet was before the fight. You lost subs, they lost fighters. There is a chance that the enemy fleet is too weak to withstand yours now, and if not the next air strike will probably achieve that. As soon as the enemy fleet has been sufficiently weakened you can eventually forget the air strikes and move your whole fleet in for the final battle. Every time you trade a sub for a plane, cruiser, or battleship you are altering the balance of power between the two fleets in your favor. In an air strike, the more subs you have the more rounds of combat you can fight. You usually only have enough subs for 1 round of combat, but later in the game it is possible that you have enough subs to protect your planes for multiple rounds of combat. In these cases you can do serious damage to the enemy fleet without exposing your own to any real danger. Subs are the infantry of the sea, there is little difference between 8 Infantry and 4 fighters in Moscow and 8 Sub and 4 Fighters in Hawaii. The main difference is that the Infantry and fighters in Moscow will sit there and wait to be attacked, while the subs and fighters will attack the enemy as soon as he comes within range. The combination of subs and airplanes are defensive attackers.
You Japanese players need to trade some of those ground units for destroyers and subs to protect your fleet. I can’t count the number of times I have watched the IJN sit there with the US player having the power to hurt it bad, sitting with within range, but not realizing that was the case. The initial Japanese fleet will get hurt badly by the turn 3 US navy if it doesn’t add some protection on turn 2. All those nice ships and planes need at least 2 destroyers and 2 subs for protection (Japan eventually wants at least 4 destroyers and at least a number of subs equal to the number of fighters on their carriers). The starting Japanese navy is essentially naked, and most players just leave it that way. This is why the IJN usually loses when they finally fight. The US player built a lot of protective ships early on out of necessity, so when the fleets finally meet those 3 or 4 extra escorts make all the difference and the Japanese player is left insisting he must have rolled bad because he had an extra carrier. The way the dice actually play out, once you’ve got 3 or 4 carriers involved then subs and destroyers actually become more useful in the big fleet battle than an extra carrier. They keep the big numbers rolling longer where the less protected fleet begins losing the big numbers early. Once you have enough protection, relative to the size of the enemy fleet and land-based air that is within range, then adding more carriers again becomes better than more escorts.
Fleets are highly defensive in nature. When two fleets are equal in size they cannot enter within range of each other. If the fleets are well designed, the one who enters range first loses. This means that fleets exert a strong zone of control within a 2 space radius of where they are, due to the strike range of their subs/destroyers and planes. Another way of putting it is that a carrier fleet provides coverage of spaces within that range.
So, for example, with this US fleet in Hawaii facing the 3 carrier IJN fleet in the above example, the US could safely retake the Philippines (if it is empty) and probably hold it for a turn or 2 or maybe for the rest of the game.
All they need to do is sacrifice a transport to get 2 inf there.
To retake it the Japanese would have to sacrifice 2 transports, or have a bomber in range to help 1 transport, because any naval units they send there will die to the air strike we just covered. In fact, attempting to re-take Philippines is usually what causes the air strike we went over above they get it back, and lose their naval superiority for the rest of the game.
Once a defensive position like this has been established the player with the coverage over the islands is free to re-take them with sacrificial transports. If you have enough destroyers, you can cover the landings with 2 destroyers if the Japanese don’t have any subs to strike with their planes, hoping to kill planes with your destroyers, otherwise just sacrifice the transports to take any islands you want. This effect can also be achieved with a combination of subs and bombers. Once in place, it just isn’t safe to approach such a position without at least 4 subs and/or destroyers defending the fleet. The Japanese don’t have this early on, so a US player going KGF can cause great difficulty for Japan early by placing 6 subs and 4 bombers in Hawaii. You can get by in the Pacific with subs and bombers in Hawaii, and a few transports to re-take island that this force covers. This relatively small force can seriously harass Japan for most of the game at relatively little cost. This can’t be done if the Japanese destroyer is alive and in range at the end of turn 1, but it almost always dies to the battleship. As long as the destroyer is not there, the 5 subs and 3 bombers the US can land in Hawaii on turn 2 will cause Japan problems all out of proportion to their cost to the US player. A single transport can take Philippines as soon as they are in place, for example, and the Japanese will have a hard time taking it back any time soon without sacrificing at least 1 transport to do it (or by sacrificing a significant portion of his fleet). This is a very cheap way of focusing almost all of your attention on Germany, if that is your plan, while still causing some serious problems for Japan during the early turns AND forcing them to buy at least 2 destroyers and 2 subs for the pacific fleet. It takes several turns for Japan to build enough protective subs/destroyers to safely get within range to threaten your subs unless they are willing to not build a lot of things they would normally build during the early turns. When he finally does move within range, suicide the subs into him and fly the bombers back to West US and on to Germany from there (assuming you are still going KGF).
The effect of destroyers in a fleet battle deserves mention as well. The important aspect of destroyers in a fleet battle is that the presence of an enemy destroyer means that his planes can hit your submarines. In a fleet battle this actually works against the enemy fleet as it allows you to take subs as casualties from airplanes. If no destroyer was present, all air hits would have to be taken on airplanes, but because an enemy destroyer is present all hits can be taken on the subs. There is no way around this, fleets must have destroyers, it is just the way it works and it works well, actually. This is another advantage of the sub supported air strike… you have no destroyer present, so the enemy must take all of your air hits on his planes while you can take air hits on subs because his destroyers are in the fight. Sometimes, though, such as the US have an opportinty to hit the Japanese fleet on turn 2, you have no choice and have to send your destroyers in too… but Japan probably doesn’t have any subs on turn 2 anyway so it doesn’t matter in that case.
Do this experiment with the battle calculator. Enter a typical US airstrike on the IJN. The US has a defensive position of 6 subs and 4 bombers at Hawaii and the (still not completed with subs and destroyers) turn 3 IJN foolishly enters range. We actually have a chance of winning this fight outright, which allows you to see something in the battle calculator that might surprise you.
US 6 subs and 4 bomb v IJN 2 carrier, 4 fig, 1 batship, 1 cruis = US win 15%.
US 6 subs and 4 bomb v IJN 2 carrier, 4 fig, 1 batship, 1 cruis, 1 destoyer = US win 35%.
If you add a 1 destroyer to the Japanese fleet Japan has a 20% greater chance of losing because that extra ship is there. This is because with the destroyer present the US can now take hits from the defending fighters rolling a 4, on subs that roll a 2, instead of on bombers that roll a 4. But this doesn’t mean you don’t want destroyers in your fleet, it just means that you want several of them. Start adding DDs in the battle calc and watch the percentage drop back down. More importantly, consider the trade on hits you will now make if you suffer an air strike. At least 2 destroyers and 2 subs are required for the protection of any fleet and this is very realistic.
A Note About German U-Boats:
Unfortunately, Germany is not a sub user. So close, and yet so far.
With a single small rule change subs would become a vital part of Germany’s arsenal in keeping the British navy away.
If Germany could keep 4-6 subs in SZ 5, which they can afford to do, they could cover SZs 3, 6, & 7 and keep the British navy out of those SZs. It would be really cool, and make subs a vital weapon for Germany as they should be. But the nature of subs is that they must be outside of range of enemy ships beforehand, so that enemy ships cannot enter within their range. They cannot enter range of an enemy fleet to attack, the enemy fleet must come to them.
This almost works for Germany, they can get into position in SZ 5 with 3 subs and their air force on turn 1 and keep the British navy out of important sea zones (3, 6, and 7).
It all falls apart with the unrealistic ability of a single ship to block an infinite number of ships in AA50.
This means the British can simply place a single destroyer in SZ 6, blocking the German subs, and put their navy in attack range.
The subs can’t reach the navy, so they can’t attack.
And on the following turn the British navy enters SZ 5 and destroys all of the subs.
This means that it would be a huge waste of money for Germany to try and use subs because all England has to do is sacrifice a single destroyer to kill the entire German U-Boat fleet.
This would be simple to fix with a simple rule from other naval combat games.
Instead of a single ship being able to block an infinite number of enemy ships, which is ridiculous, blocking ships should only be able to block an equal number of ships.
This rule works much better and would correct several different problems associated with blocking naval units within AA50.
With this rule if the British tried to block SZ 5 with a single destroyer the Germans would simple be required to leave a single sub behind to fight it (they could leave more if they wanted, but must leave a number of ships equal to enemy blockers as they pass through that SZ) while the rest of the subs continue on to attack the UK fleet. The blocking rule is the only major problem remaining in A&A naval combat, and it alone prevents subs from being useful to Germany.
With the picket force rule in place, naval combat in A&A would work very, very well and Germany would be buying subs every game.
