Yes, MAD has nothing necessarily to do with noise, but the accuracy of MAD has been hotly debated IRL and for games alike.
i have heard one source say that use of MAD has fallen out of favor since the mid 80's due to the degauzing of subs having such an affect on MAD ability to detect them when deep, and that sonar buoys are the go to item
I have also heard that MAD is ineffective in...
1. deep water even when you are buzzing the surface because it often cannot detect deeper than 900-1500 feet depending on conditions sometimes shallower
2. coastal waters because of the erroneous signals received from the sea bed, wrecks, etc
3. extreme latitudes because of the need to align the aircraft as perfectly as possible with the mag field of the earth to get it to work right and if you deviate from this, you can sometimes even detect your own aircraft.
i have also read, from a former P-8 pilot, that finding a submarine with MAD is a lot trickier and time consuming than one might think. and that in deep water, even if you narrowed down the submarines location to a 30 mile by 30 mile area, it would take you 2 or 3 hours to run a ladder pattern, and at an altitude of 200 feet you are burning through fuel very quickly in a turbine engine and would likely have to leave the area if you didnt find anything on your first sweep. if the water is very deep you would have to be lucky enough to fly right over the sub's hatch to get a reliable reading.
it was also pointed out, that if a P-8 had a good idea of the location sub to begin with, they could detect them using MAD with near 100% accuracy, every time.
so i imagine MAD is a difficult thing for the devs to simulate accurately.
but it is frustrating that there you are, lurking along for 45 minutes, everything is setting up just right for you to destroy this convoy and all the sudden you have a torpedo zooming straight down at you. (followed shortly thereafter by a dozen more lol)
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