Алистер Маклин - HMS Ulysses

It is almost impossible for one single explosion, or even several in the same locality, to destroy or incapacitate all the dynamos in a large naval vessel, or to sever all the various sections of the Ring Main, which carries the power around the ship. When a dynamo or its appropriate section of the Ring Main suffered damage, the interlinking fuses automatically blew, isolating the damaged section. Theoretically, that is. In practice, it does not always happen that way – the fuses may not rupture and the entire system breaks down. Rumour – very strong rumour – had it that at least one of HM capital ships was lost simply because the Dynamo Fuse Release Switches – fuses of the order of 800 amps – failed to blow, leaving the capital ship powerless to defend itself.

It is regrettable but true – the Home Fleet squadron was almost always too late. The Admiralty could not be blamed – the capital ships were essential for the blockade of the Tirpitz ; and they did not dare risk them close inshore against the land-based bombers. The long awaited trap did eventually snap shut; but it caught only the heavy cruiser Scharnhorst and not the Tirpitz . It never caught the great ship. She was destroyed at her anchorage in Alta Fjord by Lancaster bombers of the Royal Air Force.