▁integrated ▁to ▁power ▁bow - th rust ers ▁for ▁slow - speed ▁man œuv ring , ▁until ▁a ▁ref urb ishment ▁programme ▁by ▁B AE ▁Systems , ▁that ▁ran ▁from ▁ 2 0 1 0 ▁to ▁ 2 0 1 8 , ▁replaced ▁the ▁D elt ic ▁with ▁C ater p ill ar ▁C AT ▁C 3 2 ▁engines ▁in ▁the ▁eight ▁remaining ▁commission ed ▁Royal ▁Navy ▁vessels . ▁ ▁Railway ▁use ▁▁ ▁The ▁" D elt ic " ▁engines ▁were ▁used ▁in ▁two ▁types ▁of ▁British ▁rail ▁locomot ive : ▁the ▁ 1 9 6 1 – 6 2 ▁built ▁class ▁ 5 5 ▁and ▁the ▁ 1 9 5 9 ▁built ▁class ▁ 2 3 . ▁These ▁locomot ive ▁types ▁were ▁known ▁as ▁" D elt ics " ▁and ▁" B aby ▁D elt ics ", ▁respectively . ▁ ▁The ▁Class ▁ 5 5 ▁used ▁two ▁D 1 8 - 2 5 ▁series ▁II ▁type ▁V ▁D elt ic ▁engines : ▁mechan ically ▁blow n ▁ 1 8 - cy l inder ▁engines ▁each ▁r ated ▁at ▁ ▁continuous ▁at ▁ 1 5 0 0   r pm . ▁The ▁Class ▁ 2 3 ▁used ▁a ▁single ▁less ▁powerful ▁ ▁nine - cy l inder ▁tur bo charg ed ▁T 9 - 2 9 ▁D elt ic ▁of ▁. ▁ ▁Six ▁out ▁of ▁the ▁original ▁ 2 2 ▁' D elt ic ' ▁locomot ives ▁surv ive , ▁four ▁of ▁which ▁have , ▁at ▁various ▁times ▁since ▁ 1 9 9