ASW

[Gratch1111]

So I have 8 patrol aircraft at 100 feet all around Pearl. plus 10 ASW groups of 3 DD, AM etc in each and nothing even come close to hitting a sub. Am I missing something or is this just how it is? Basically it wont matter what you do, cant sink anything anyway

[DConn]

Results depend heavily on the experience of the ASW units. If it is early in the war, you won't be sinking much.

[BBfanboy]

You are also using your aircraft much too low. At 100 feet they would not see much area. You need search aircraft at 2000-6000 feet to initially spot the subs and ASW at 1000-2000 feet to localize the contact and attack it. Very rarely, search aircraft will spot and attack a sub, usually if the weather helps hide the plane's approach. Are you aware that ASW aircraft search out only half the range you set (because it is an intensive search)? And if you consider that six X forty NM hexes around PH = 7536 Sq. Mi. , 10 aircraft is not a lot for even that one-hex range. Add another hex of range and the area to be covered becomes enormous.

[Platoonist]

When your destroyers eventually get upgrades (K-guns, Mousetraps, better radars) odds improve. A lot will still depend on crew experience and leadership. But, even with those it not an everyday occurrence.

[Wirraway_Ace]

If this is early war, patience is needed. Unless a pilot is very experienced (80+), pilot skill in ASW must be 70+ to generate attacks. As the Allies you will have neither at the beginning.

Search arc, number of aircraft and range are all are important considerations. The ASW game mechanic is based on the naval search routine (I believe) in which a single aircraft is assigned a single 10 degree arc out to half the set range in a clockwise rotation in the morning and afternoon phases. If you have eight aircraft set to 60% patrol on an arc of 270 to 360 degrees, they will actually only cover from 270 to 330 degrees during a full turn and will cover that same area the next turn. If no arc is set, the aircraft are sent out on random arcs up to the number of aircraft * patrol level (%) / 2 (half morning phase and half afternoon). As the aircraft gets further from the base, the chance of contact is diminished by the tyranny of geometry (the area to search at the end of the arc becomes enormous).

Altitude is also an issue. The amount of sea that can be observed at 100ft is tiny when compared to higher altitudes. I have seen other forum members recommend a 100ft altitude for ASW missions. I am suspicious of that advice. I use 1000-3000.

Enemy tactics (the subs not staying put, and sticking to deep water), experience and tech (Allied air search radar upgrades to the Gatos/Balaos) all play into the chance of both detection and attacks.

As far as your surface USN ASW groups, they need to gain experience and get their upgrades before they become effective at sinking enemy submarines in deep water hexes. The RN escorts are more competent.

[Torplexed]

If I recall, of the 128 Japanese subs sunk during the war only 16 were lost to aircraft or a combination of surface ships and aircraft. By contrast, in the Atlantic, the Germans lost about 294 U-boats to planes alone. But a lot of that was due to the Bay of Biscay becoming such a deathtrap to cross by 1943 either when starting a patrol or ending one. They were basically crossing RAF Coastal Command's doorstep.

Plus, the Germans built well over a 1,000 U-boats so there were more to kill.

[GetAssista]

Unless a pilot is very experienced (80+), pilot skill in ASW must be 70+ to generate attacks. As the Allies you will have neither at the beginning.

It is not nearly this strict in the game. Attacks are just less frequent with less experienced and trained pilots. Much less in the beginning when you have neither of the skills on your pilots as an AFB, but they still happen now and then. Also keeping subs down by spotting them and making them react is also useful, I believe it is not the registered attack itself that makes the sub react and waste time

[Gratch1111]

Re Fanboy, I have read on the forum that 100 on asw Patrol is the best so that is what I did, but I agree, to me IRL it sounds to low. But I will add som naval and ASW search on higher altitude, like 1-2000

[Wirraway_Ace]

Unless a pilot is very experienced (80+), pilot skill in ASW must be 70+ to generate attacks. As the Allies you will have neither at the beginning.

It is not nearly this strict in the game. Attacks are just less frequent with less experienced and trained pilots. Much less in the beginning when you have neither of the skills on your pilots as an AFB, but they still happen now and then. Also keeping subs down by spotting them and making them react is also useful, I believe it is not the registered attack itself that makes the sub react and waste time

GetAssista
I don't disagree with your premise, though I have not seen it. In my experience, the 70 ASW skill is like a light-switch, a step variable, very different from other aspects of the game engine in which hit probabilities appear in a more linear relationship to skill (though always affected by other factors and a random). When I have air units with some pilots over 70 ASW skill and some under, the attacks seem to always come from the 70+ crews based on checking after the turn which received experience gains.

I generally rely on NAV SEARCH missions to detect the submarines and route my ships around them until I can train-up dedicated ASW squadrons.

[Wirraway_Ace]

I went back and looked at the major ASW threads back to 2009, including the few developer comments and those of the usually reliable Alfred. This is a summary by the latter in 2015:

1. Look up Table 20.1.2.1 of the manual (pages 280-284) to see what tasks the different ship types can do.

2. Read s.6.1.1.1 of the manual to see what the different types of Task Forces are capable of doing.

3. Read pages 150-154 of the manual to see the different types of air missions available to aircraft.

4. You need to set at least one air unit to conduct as it's primary mission, ASW. This is to raise the DL (Detection Level) on the sub. Read chapter 10 of the manual for detection. A detection level of 1 will show the sub icon on the map, it will be useless in terms of actually prosecuting an attack on it.

5. The air unit conducting ASW must have it's pilots trained to conduct ASW. It will be useless if you have pilots highly trained for ground attack but with poor stats for ASW. Plenty of threads deal with pilot training. Also read the Addendum provided in a very early patch.

6. Set up a dedicated ASW Task Force, with the appropriate ship types, to patrol and hunt down subs which have been spotted by your flyboys.


Many players make the mistake of thinking the game code should operate according to their preconceptions. It never turns out satisfactorily for them.