Hi all I have a lot of questions on how British submarines returned to base safely, avoiding being attacked by their own side. I’m guessing they had to surface at a pre designation position, at a pre-determined time, for, say a A/S trawler to lead them back into base. So, how far out might their surfacing position be, what recognition signals, signs might they display, how close might the trawler be to them on surfacing, were there transit lanes to and from the surfacing point Would the position change periodically or be individually different for each submarine, was there an overall time frame for this, before the position expired, was it set at a particular time of the day, ie just after dawn? Regards Fatboy Coxy
I'll see what I more can find when I return home but IIRC a lot of these things were prearranged as part of the patrol plan. Routes in and out of patrol areas, actual patrol areas, recognition signals and any linkups between vessels were all pre-assigned and other Allied forces were alerted. RN submarines also had scheduled radio checks, not as frequent as U-boats, in which information could be updated.. Deviating from the assigned routes and procedures could have serious consequences, one of the best examples being the blue on blue of HMS Oxley and HMS Triton in 1939. HMS Oxley - Wikipedia Board of Inquiry notes here: The Loss of HMS Oxley 1939 | Naval Historical Society of Australia I'd recommend this book too: https://www.amazon.ca/No-Room-Mistakes-Submarine-1939-1940/dp/1848322062
