if you put a sub at 55ft deep, it will continously transmit link. Can't tell if it actually raises masts or not. All friendly AI subs that start at 55ft will show up on link early in the game. They are pretty quick to launch TASM if you link to them. I imagine it works at a bunch of different depths but thats the one i used.
i put a SSM site on an island one time. Then i stuck a seawolf at 55ft deep approx. 2-4 miles from the SSM site. Somehow the AI actually promoted the SSM site to link (i guess its using ESM to detect it, not sure if it actually raises the mast). Then another AI Seawolf lauched a TLAM at it. Pretty kewl :|\
i didn't realize that barrier included a depth change and link promote, thats neat.
