Its in the QA dock in Cardiff Andy or it was yesterday,it came in with a Dutch patrol boat on friday and apparently it was just in front of our boat all the way from Flatholm but we didnt see it.
two of us sailed up today from barry and as we was aproaching cardiff if it was being towed out by two tugs then after it got so far out the tugs let it go and it sailed away on its own power. when i find my phone lead i will upload a few pictures.
I used to work on sub com systems 25 years ago, they used to have to stick an aerial up and do all the transmitting and receiving in one go. They used VLF - very low frequency which actually bounces round inside the atmosphere so you can radio a sub anywhere on the planet. I expect things have moved on now though.
They used to, that and good old fashioned charts! I expect technology has moved on now though, after that grounding last year there is clearly a lot to be said sticking your head out of the top and having a butchers!