Had the honour to serve with them back in the eighties on the S61's. It's not the equipment that does it, it's the person - these people are the best. They make it look like a walk in the park.
I remember doing a sub transfer off bermuda with them to collect a seriously injured submariner. The sub called up and said it would surface to conning tower depth for x minutes only due to operational reasons. We had to find it.
It was night and the casualty was 186 Nm's out. The navigator flew us there bang on the numbers using the old weather radar in the back of those old hulks! Mind blowing guys!