I'd say scrap that feature of the mission editor altogether... its probably taking crap values from the database.
Your personal experience is much more helpful, also the acoustic conditions can vary *so much* that the mission needs to be extensively tested from the initial creation onward.
Basically, start with the idea that the detections are going to happen around 10-15nm for modern subs against quiet subs and then work from there.
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LW
 
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