Appendix I: List of RN Submarines in the 1901 to 1936 Programmes
The dates given in this list for laying down and launching can be taken as reasonably definite but variations have been seen in dates for the completion of some vessels. This is probably due to different procedures in reporting e.g. the date of commissioning, the date of handing over from the builder or the boat leaving the builder's yard. This applied especially for completions during the 1914 - 18 war and, under the circumstances is not expected.
- The dates given for 'Taken out of Service' for those vessels lost at sea and not salvaged as mentioned in the remarks column are exact dates. For the remaining vessels the date given is that of the issue of CB1815 from which the name of the vessel has been removed. CB1815 was issued quarterly up to April 1925 so that up to that date the vessel would have been removed from the Active List within the preceding three months from the date shown. After April 1925 CB1815 was issued half yearly so that the vessel would have been removed from the Active List within the preceding six months from the date shown.
- In the remarks column the following abbreviations are used.
- LAS Lost on Active Service
- (S) Salvaged