From: PDX (and now) London, UK
If you're not playing a mod that reduces ASW many of the above suggestions are very good. Killing subs is the goal for sure, but making them ineffective is also really helpful. Good search, both day and night keeps them at bay. The higher you raise their detection levels, the less likely they will be to have a successful attack. Also, your ships will be more likely to attack them. Some other tips:
1. Change your ASW ship captains to ones with good aggressiveness and naval scores. Above 60 is preferable. You won't have enough of those for all ASW ships. Also in a valuable transport TF (i.e. with lots of troops on board) it's better to have a TF commander with good naval score at least, which can help them avoid combat.
2. Make sure you have converted ALL Ansyu-C xAK to PB, and these will add a good number of escorts. The more escorts you have, the more likely for the sub attack to fail or the escort to be hit rather than the AK/AK/TK. There are also two other smaller classes, the To'su (which are 10 knot before conversion but 12knot after, so good with the Aden class and others) and the Kiso-E (11knots) that convert to PB. Most players convert some of these, but also some to ACM and other types. The ACM are needed to keep the mines from disappearing in port once laid, so they will help in the role against subs as well.
3. Mine between islands, on the straits where these subs move or try to choke off transport. Remember though that offensive mines (anything not laid in your own base hex) can be hit by your own ships as well.
4. Your pilots wil not be trained in ASW in the beginning. It takes a while. Start at least one IJAAF and one IJNAF training squad dedicated to produced ASW pilots. Train ASW (to locate and attack them) and low naval skills (to be able to hit them). Many players also train while on the ASW mission by setting groups to 40% ASW 40% training 20% rest at 1k altitude. I always run float plane search in infested areas at 1k as well to increase the number of attacks t the expense of more ops losses.
They will just keep getting better. I have run a few short tests, and about 1/4 of those notices of hit subs in the beginning few months seemed to actually be hits. But a hit might only mean 30 float damage on a sub, so it would just go home for repairs and come back later. Still, that gets them out of the shipping lanes for a few weeks.
5. Send ships through the shallows as much as possible to get subs in disadvantageous territory. The Type 95 DCs will not hit US subs at all 95% of the time in deep water hexes. This is based on the performance of early IJN DCs in the war and the good diving depth of US subs. So for ASW TFs in the deep water use only DDs with Type 95-mod2 or Type 2 DCs. Always make these 4 ship TFs if possible and run them right over known sub patrols with active search (day and night) in the area. The DDs will very rarely be hit by a sub if there is good search in the area, and if attacked will usually stand a good chance of at least damaging the sub if they have captains with high aggressiveness.
6. If you need more search, take off the second group of float planes from the CAs and re-size them on an AV or a CS to get a 9 - 24 plane group. Build more Jakes. They have 4 bombs, so are more likely to hit something than other float planes, plus good range at 8-10 hexes. In the beginning Lilys (4 x 100kg bombs) work well for IJAAF ASW, range 9-11, or Annes (only one 250kg bomb) in a pinch, range 6-8. Sallys and Helen Ia will likely be your best SW planes for IJAAF once you have enough of them. Kates are the best ASW plane period for me, and It'a good reason t build more of the B5N1 early to use up the engines. They also have multiple bombs (2x 250kg) and more maneuverability than the 2E planes, plus good range. Remember that on ASW missions range is halved.
7. For really valuable TFs (CVs, BBs or some troop ships) have the TF follow an ASW TF, and have a built in AV, CS or CV/CVE flying ASW patrols. I also train the KB pilots to ASW when not in danger of attack. That can be risky, though, so make sure you're well away from enemy CVs if your Kates are patrolling for subs.
< Message edited by obvert -- 10/6/2012 10:54:53 AM >
"Success is the ability to go from one failure to another with no loss of enthusiasm." - Winston Churchill