well any attacks i carry out (or try to) on conyoys, task forces or a flock of seagulls, i never travel above 2 knts and always silent running from below 7000 range. above that range i can travel a little faster 4-5knts, but you just have to be as silent as possible. imo 4 knts at 2000 range is too noisy, silent running automatically reduces your speed to what is assumed is relatively silent (3 knts) i drop down to 2 knts to be sure.
if you use this technic you might find you can get very close without being detected (ive got as close as 1000 and still not been picked up) you just have to hope that your intercept calculations have been precise, if not then its start all over again time.
