Basic Details Surname Blackburn Forenames John Gender Male Information stated on memorial War Military Service Served or died Died Honours DSC Notes Commanding Officer. Submarine sank off Alderney, Channel Islands after accident Primary Service As stated on memorial Unit (Primary - Stated) HM Submarine Affray Rank / Title (Primary - Stated) Lieutenant (Commanding Officer) Our References Service (Primary - Our reference) Royal Navy Unit (Primary - Our reference) HM Submarine Affray Rank / Title (Primary - Our reference) Lieutenant Death and Burial details Country of death England Town of death Off Alderney Country of burial At Sea Year of death 1951 Month of death April Day of death 16 Manner of death as stated Killed when submarine sank Manner of death reference Missing