Q: what are the characteristics of the various weapons in game? What's the difference TLAM and TASM. etc.
US Torpedoes
Mk16 - old WWII torpedo, no homing capability. Max speed 46 knots, range 11.500 yards. After launching it will turn to desired gyro angle and then run straight ahead and explode on contact. Easy to miss with or evade by target, basically needs to be fired point blank.
Mk37 - basic homing torpedo, used in 1968 campaign. Max speed 23kn, range 23.000 yards, seeker range 950yds. Needs to be fired from slow moving sub (don't ram your own torp!) at very close range as it can be evaded or outrun by many targets.
Mk48 - advanced homing torpedo, used in 1984 campaign. Max speed 60kn, range 35.000yds, seeker range 4.000 yards. Great fire and forget weapon, but can also be steered by wire manually.
US Missiles
UGM-84 or Harpoon - medium range smaller anti-ship missile. Fired from under water, flies close to surface. After reaching activation point it will switch on search radar, locate largest target in seeker area and try to hit it. Can be shot down by anti-air or CIWS defenses on target. Optionally you can configure it to perform "pop up" maneuver before hitting target, which should make it more difficult to intercept. Larger targets will usually take 2 hits to sink.
Tomahawk Anti-Ship Missile or TASM - long range anti-ship cruise missile with large warhead. Slightly faster than Harpoon, large warhead is good against capital ships, but easier to shoot down due to its size.
Tomahawk Land Attack Missile or TLAM - long range land-attack cruise missile. Used for port strike missions. Note: against warships it is best to try and get missile shot on bow or stern of the target as the CIWS coverage there is the weakest, while sides are usually better protected. Good trick is to send a torp and when the ship goes to evasion, it will usually turn away from the torpedo and try to run away. That's the right time to send a Harpoon up his a##