ROUTINE SIGNALS SENT BY A SUBMARINE AT SEA

[made in the period 1950's to 1970's - and maybe at other times too!]

1. ON SAILING

NEXT OF KIN - A SOA [Submarine Operating Authority] usually embarked in a Depot Ship, or a base [Fort Blockhouse for example], known as 'Captain First Submarine Flotilla' for example and abbreviated to SM1, holds the next of kin details book for all crew members of every boat in that flotilla. They are continuously amended/up dated as circumstances dictate {change of address, getting married so change of NOK, not getting married but NOK dies and a new NOK is nominated - most unmarried men declared one of their parents to be their NOK}.  Sometimes crew members are left in-board because they are either ill or there is a compassionate case for them not going to sea. In that case, their place is taken by a member of the Flotilla's Spare Crew.  On occasions, passengers are taken to sea [ASW training classes; Submarine CO'S Desig undergoing their Command Course/examination called the Perisher; dockyard personnel; Royal Marine personnel, usually from the SBS <Special Boat Section> plus others doing trials.

The first signal sent has two sections. In Section A, all crew members not sailing are listed. In section B, spare crew submariners and all other temporary personnel are listed showing their full NOK details.  This signal is kept inside the boats NOK book by the SOA until the boat's safe return to harbour or until those in section B are transferred to other vessels or to terra firma not connected with the boat's base port.

2.  DIVING SIGNAL

DIVING SIGNAL - is the second signal sent - many aspects of the patrol to come are resolved before sailing negating the need for unnecessary signals. When the submarine sails, it is for all practical purposes watertight as is a surface vessel. At some point after sailing, the Command is given to "open up for diving".  On completion of this evolution, the boat is still watertight but on the pulling of levers and the opening of valves, sea water is allowed into the ballast tanks which makes the boat bodily heavier, leading, with the use of the hydroplanes, rudder and propellers turned by a electric motor and not by a diesel engine, to a controlled dive under the waves. Before this can happen, the Diving Signal is sent to the SOA, giving time of the first intended dive; the geographical area; the duration of the dive and the reason for the dive. During this period, the submarine can dive or surface at will to meet operational requirements.

3.  SURFACING SIGNAL

SURFACING SIGNAL -  On completion of the dive period [stated in 2 above], this signal is sent to SOA and any other addresses on the diving signal. It contains the one word only namely SURFACED.   If the boat intends to dive again, a new Diving Signal is required.

4.  CHECK REPORT

CHECK REPORT -  If in 2 above, the dive is for a considerable period of many hours, a pre-sail brief would have laid down the rules for contacts with the SOA at specific intervals. These can vary depending upon the nature and reason for the patrol, ranging from 12 hours to 24 hours [not usually longer]. Again, as in  2 above, the submarine can dive and surface at will. At the agreed interval of time, the submarine will either surface or come to periscope depth and raise its main wireless transmitting aerial to send a signal containing just the one word CHECK to all addressees on the diving signal. The submarine is then allowed free range until the next agreed time point is reached. Thus, the diving signal may result in several CHECK reports being signalled, each in their turn the equivalent of the surfacing signal in 3 above. If the CHECK REPORT timing is missed or radio conditions are adverse denying a contact ashore, the SOA 'starts the clock'  hoping for that vital contact.  When the clock stops [alarm is sounded] a SUBMARINE MISSING OR LOST procedure is started, which is not covered here in this snippet.

5.  CHOP SIGNAL

CHOP SIGNAL -  Whilst on patrol, a submarine operates in a known geographical area commanded by a flag officer. Sometimes, a submarine will stay in the confines of that area, but on other occasions, a pre-planned change of area takes place.  The pre-sail brief will have stated whether the submarine should notify the relevant flag officers when the CHOP-LINE had been crossed.  If it is a stated requirement, then on crossing the line, a signal bearing the one word CHOP is signalled ashore with all relevant flag officers as addressees. Sometimes, each flag officer had his own communications facilities, fleet radio broadcasts for example. When appropriate, the CHOP signal could include the new broadcast, its readability and the first number received, adding the closing time of the former broadcast and the last number received on it.

6.  LOGREQ SIGNAL

LOGREQ SIGNAL -  All fleet units, whether surface or sub surface, had to submit by signal, a LOGISTIC REQUIREMENT, at a given number of hours before arrival at an Allied  naval port/base.  To see the proforma of a Logreq look at pages 29 and 30 of this file http://www.godfreydykes.info/GUIDE%20TO%20USERS%20OF%20NAVAL%20COMMUNICATIONS.pdf - it is quite interesting to see what is covered!

7ETA SIGNAL

ETA SIGNAL -  As in 6 above for all fleet units, this signal sent usually 12 to 24 hours before arrival, prepared the dockyard/port services, for the boats arrival alongside.  Boats rarely secured to a buoy. It was the normal practice that when the boat was visiting a port which didn't have suitable naval or military facilities/accommodation, then civilian accommodation was provided at public expense. In all such cases, the officers used 4/5 star hotels, senior rates 3/4 stars and the junior rates 3/2 stars, but the frugal paymasters {?} would, if given half the chance, do-down to the lower star ratings shown above.  However, in my experience of round the world such luxurious treatment, I always remember having excellent shore accommodation, which after living in a diesel boat of WW2 design/build, wasn't hard to better: nevertheless, always a 3 star at the very least. Speak with the 'right people' and more wonders evolved and of course at public expense. Being a submarine of those archaic times, we didn't have SSB voice, so even assuming that we had an opportunity which on the surface {big ?} we couldn't, like surface sailors 'phone home to our wives and families, even though it was an expensive thing to do. So, I used to send a telegram from the hotel [not to mention post cards and the like} and on the odd occasion, would book and subsequently make a Cable and Wireless phone call home to my wife: all on the boats account please which was paid not by the boat in situ, but many weeks later from hundreds/thousands of miles away!