That's the last time I'll complain when my boys leave the toilet seat up...
Musings from the creatively maladjusted. What writers write when they 1) aren't writing, 2) are avoiding writing, 3) need a word count to convince their spouses they are writing, 4) are between deadlines or 5) aren't distracted by the Google demon...
Subs are not well-suited to exchange blows. The idea is shoot first and kill; shoot and go.
There are two kinds of sonar, active and passive. Active sonar is older. You send out a signal and wait for a ping. That gives you instantaneous bearing and range. The problem is that it's fairly short range, and more importantly, it gives away your position. A modern hull mounted active sonar can produce hundreds of thousands of watts of sound energy, reaching up to around 250 decibels (dB). Compare that to the sound level of a jet engine at 30 meters distance, which is just 150 dB! Active sonar may also be your only useful choice when dealing with diesel-electric submarines, since these are extremely quiet when running on their batteries. Here's an (alarming) analogy to get an idea of just how difficult: Try to locate a refrigerator by listening for it from outside the house. With active sonar you can hear out to ten miles, but you can be heard out to 20 miles.
Passive sonar is what the Navy generally uses today. Passive simply means listening to what your instruments can hear. Passive gives you bearing but not range, and it takes a long time to convert this to usable information. The temperature structure of the ocean dictates how sound moves through it. It puts bend on the sound. Submariners map out the temperature and velocity structure of the water to figure out where to hide. Detection is difficult. It's hard to classify sounds. Localization is also difficult. Tracking is easy if you have steady contact, but with a lot of turning, this is difficult too. Engagement depends on knowing where the other guy is.
Because subs have to surface to communicate, they don't work well with others. The ability to communicate while deep is the naval Holy Grail.
Mazin Al-Shihan, director of Baghdad's Displacement Committee, on his plan to pay men to marry Iraqi war widows and take control of their finances