My own tests showed that the OHP FFG could detect a transiting 688i (9 kts) better than the 688i could detect the FFG traveling at the same speed. The distance used was ~7nmi. Both disappeared from one another's tracks at 2 kts or less, but the FFG could travel up to 5 kts before being detected while the 688i was limited to 2 kts. This is towed array vs all the 688 sensors - I think the sphere was picking up broadband and the towed was getting tonals from 60hz while the ffg was transiting.
Just fyi. This is for ffg vs sub and sub vs ffg obviously, and may not be applicable to subs finding subs. I also wasn't playing around with layers much, but from experience I've not found a layer in Dangerous Waters which the FFG couldn't get the towed array below. Is that just lack of experience?
