Don't know if anyone here is into Cold War, or Ultramodern Naval Gaming, but there's a free set of simple rules available on the "Conn.... Sonar!" Facebook Group.
It's primarily geared to sub vs. sub combat, but ships, helos, and aircraft are being added on as well. Cards used for play are simple enough to permit you to modify them to your liking, and create vessels, and aircraft not included thus far.
Worth checking out, if you have any interest, since the price can't be beat, and they're geared to simple, beer and pretzels gaming type play, at the local club.
They're designed for when the opponents get down to the nitty gritty of combat, as opposed to endless searching for elusive, or non-existent targets.
I suspect for those wanting that type of game too, it shouldn't be too hard to bolt on something to make that work, for solo, two-player, multi-player, or GM'd games. Having a GM available to run double-blind, hidden movement games would be best, but there are workarounds to address that, most people are aware of.
A lot of people are using 1/700th scale vessels, but you can use whatever you have, including 1/2400th - 1/3000th scale subs and ships, if you desire.