Originally Posted by SeaQueen
It depends on which type of quick mission you're performing. Is it the "area search" or is the "barrier search." If it's the "area search" then you want to plot a course through the area such that the area covered by your primary search sensor (usually your towed array) is equal to the size of the area. Usually you can do this by driving a ladder pattern. The spacing of the various waypoints depends on how far you think you can see. You can guestimate it from experience or you can do what I do, and use the mission editor. If you look in missions I design, I actually try to include that information as part of the briefing.
It doesn't really matter much what you do when you're in the box, statistically, though, because complicating factors such as target motion, maneuvering for TMA, flight ops, and unmasking weapons, means that you the area covered will almost always overlap itself a little bit no matter how carefully you plan the search. That has the effect of making almost every search equivilent to random searching. The formula for the cumulative probability of detection as a function of time is given by the Koopman random search equation.
Pd = 1-exp(-2R v t / A)
where R is the sensor range, v is your speed, t is time, and A is the size of the area you are searching. It's just the exponential distribution. You can find detailed derivations of it in Wagner's Naval Operations Analysis, or Koopman's Search and Screening. You might also be able to find it in SAR manuals. Search tactics for ASW and search tactics for search and rescue are basically the same ideas. You want to find something where you have only a rough idea of it's location as efficiently as possible. From that you should be able to make a pretty good estimate of how long it'll take you to find him, on average.
For the case of the barrier quick mission, you just need to drive back and fourth between the two waypoints. The probability of you succeeding in detecting a target depends on your speed, your sensor range, the length of the barrier and the target's speed. In the literature I just mentioned, they give formulas for the Pd of barriers as well. By making assumptions about the target's speed and your sensor range, you can often optimize your speed to maximize your probablity of detection, given the constraint of wanting to minimize your noise level.
Checking your baffles isn't necessarily the first thing you do, but it can't hurt. I actually have a random number generator in an Excel spreadsheet, to generate things like random times and bearings, so that I don't get too predictable. Some people do it regularly. One of the good things about your towed array, though, is that it gives you pretty good coverage of every place but the endfire forward. The baffles clearing thing is mostly an issue with submarines that lack a towed array.
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