Excellent primer by Mr. Showtime from the Grog thread.

If you get a grasp on the following, you know 90% of what it takes to play Command.

General

Using active sensors will usually instantly betray your approximate position to the enemy, even if they’re not close enough for you to detect them.

If you don’t have any idea what something is, check in the database viewer. You mostly care about sensors, weapons, and how old something is.

Try to have less valuable things between your valuable things and stuff that wants to kill them.

The best possible situation to be in is one where you know where the enemy is and they don’t know where you are. To that end, always use (and protect) your most valuable recon tools while trying to hunt down the enemy’s.

Submarines

Periscope depth lets you use your ESM, radar, and periscope (obviously), but makes you very easy to detect. In calm sea conditions, you can usually hear and be heard at extreme distances when at periscope depth thanks to strong surface ducts. In bad weather, this is less true.

Shallow depth is good for keeping track of the surface without being ridiculously easy to detect. You can dive beneath the layer to hide from hull-mounted sonar, but this will expose you to a boat’s towed array, if it has one (they’re usually trailing them beneath the layer).

Just above the layer is ideal for anti-submarine warfare. Your towed array (if you have one) will listen beneath the layer, and your passive hull sonar will listen above. You can also go faster without cavitating.

In the layer makes it hard for surface ships to detect you, but makes it hard for your passive sonar to detect anything. Your towed array will listen beneath the layer if you have one.

Just below the layer is a bad idea and you should never be there unless you’re just passing through on your way to another depth. You are in the SOFAR channel, where sound travels incredibly well and where everyone is listening for it. If you don’t have a towed array sonar, sitting still here is sometimes okay, as it lets you make the best use of your hull sonar against other submarines.

Real’ fucking deep is a good place to be if you’re planning on traveling. You can go very fast without cavitating, and you’re not as loud as you are if you’re just below the layer. As a bonus, being close to the bottom makes you much harder to see on active sonar.

99.9% of the time, there is no good reason to use active sonar.

Your passive sonar can’t listen very well if you’re going faster than like ten knots, and going fast makes you way louder.

It takes a while for submarines to find and classify passive contacts. Unlike active sensors, passive sensors can take some time to pick up contacts.

Ships

Two ships close to each other are more than twice as powerful as one ship.

Ships are completely blind to low-flying aircraft, missiles, and other ships until they come over the horizon. Ships love helicopters and maritime patrol aircraft because of this.

Ships that are moving can’t find submarines, but are great at finding incoming torpedoes. Ships that are moving very slowly or standing still can find submarines, especially if they have a towed array. If you think there might be submarines, set up ASW patrol missions with helicopters and occasionally stop your ships to let them listen. Some ships have a special thing called Prairie/Masker, which makes them quite a bit quieter–it’s not enough to make them truly sneaky, but it helps.

find submarines, especially if they have a towed array. If you think there might be submarines, set up ASW patrol missions with helicopters and occasionally stop your ships to let them listen. Some ships have a special thing called Prairie/Masker, which makes them quite a bit quieter–it’s not enough to make them truly sneaky, but it helps. The missile defense value a ship has is a pretty good way of judging how capable it is at shooting down missiles and aircraft. The number is approximately how many crappy anti-ship missiles you need to fire at a ship at once to sink it, so it’s useful for both defense and offense (if you positively identify an enemy, you can click it to see it in the database).

In general, Soviet/Russian ships have extremely powerful anti ship missiles, but their naval SAMs aren’t as good as their American counterparts. American ships have extremely powerful air defenses, but aren’t as good at killing other ships. Your goal as the Soviets is to detect and identify enemy ships, then coordinate to hit them with a barrage of missiles. Your goal as the Americans is to use your powerful air defenses to sweep the sky clean and protect your stuff while your aircraft and submarines sink enemy ships. These are not universal truths, but they’re close enough.

Jamming can be immensely helpful.

Aircraft

Not that much to say here, planes is planes and the database viewer should tell you all you care about.

AWACS/AEW&C aircraft are almost always the most valuable air assets you have.

Stealthy planes are royal motherfuckers to deal with.

SAMs