As an aside - I love the names of the <i>Dark</i> class of RN boats that used Deltic engines:<p><a href="https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Dark-class_fast_patrol_boat" rel="nofollow">https:&#x2F;&#x2F;en.wikipedia.org&#x2F;wiki&#x2F;Dark-class_fast_patrol_boat</a><p><i>Dark Avenger</i> probably being my favourite!