I'll give you some tips since I use bouies all the time as a Surface/air operator (Note these tips are for Stock DW):
Helicopter:
think about possible locations for the enemy sub. first drop a BT bouy to see if there is a layer. If not, lay Difar sonobouies every 5-7 miles around where you think the enemy sub may be. After the bouies go active, look at them all and see if you found him. If you did, drop a dicass about halfway down his line of bearing and maybe one at the far end, depending on location. Ping him and sink him.
If you have a layer, you will have to drop a VLAD sonobouy with every DIFAR. Do the same thing as before.
If you want to do a passive kill. When you have a line of bearing put passive sonobouies on either side of it. Update the first track and then mark him with the other 2. they should create a nice triangle where the sub is. right click and put a manual solution in that triangle and mark it a hostile sub. it's almost as accurate as doing an active ping.
P-3:
P-3s have a much easier time dealing with submarines than the helicopter because if the sub is at periscope depth, by the time he come up to shoot you, you already have a MAD/SAD on him and you're far away. when you come back a torpedo will keep him occupied.
lay the same bouy pattern as you would with the helicopter. this is better done at a low altitude. Keep you're MAD sensor on at all times, it could save your life, or end his.
when you have a line of bearing on the sub, just fly down it with the mad on and you'll find him. turn around and sink him.
The Oliver Hazard Perry:
This is the hardest because you are almost always vulnerable to the enemy subs.
Have you're helicopters do all the work or you could end up at the bottom of the ocean. using the helicopter control station in FFG, have you're helicopters lay the bouies like you would if you were flying. if the enemy is a close contact, all you really need is the towed array and auto TMA.
Note: you're helicopters can prosecute targets better than any human could. In fact, I sank a seawolf using only one difar bouy because the helicopter did almost a TMA of its own.
remember to keep you're AI helicopter moving. It only goes at 100Kts and flies at about 200-300ft. This is well within range of the SAMs on subs.
Basically, if you have a datum, cover it with sonobouies. Make him scared to so much as sneeze.
If you don't have a datum and/or the area is very large, create sonobouy nets (just a group of bouies lined up) in locations likely to be transitted or where they may be. use DIFARs and VLADs first and try to save the DICASS active bouies till you have a line of bearing. However, if he's a kilo class sub. you may have to ping the hell out of him with dicasses to find him.
The P-3 and FFG carry more than enough bouies to cover a 100 square miles. The helicopter is limited but can be resupplied at the Perry.
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