In addition, the two lines from each sensor must come in at the same time, otherwise it will not depict an accurate intercept. Also, the towed is known to produce data with a noticeable error at times. However, I have yet to figure out the conditions for this to happen. With the slim angle between the two sensors' data, any small error will have large implications for where the intersection lies. In my experience, sensors like the spherical/cylindrical or conformal don't get this noise in their data. Traditional TMA techniques are by far the more reliable method than the intersection technique. Intersection can be good for a ballpark range, but really just for contacts that are rather close where the large angle between sensors' data will far outweigh the towed bearing error.
For clarification, I was not talking about the bad towed data you get when the towed is moving around from a depth or course change. That is also something that invalidates the intersection range method. Sometimes even when the towed is in steady state, I'll get noisy data. Typically for faint, distant contacts.
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