HMS K5: The Portsmouth-Built Submarine That Dived and Never Came Back

Made in Portsmouth

Most of the K-class submarines were built by the big private yards, Vickers at Barrow, Armstrong Whitworth on the Tyne, Scotts and Fairfield on the Clyde. HMS K5 was one of the few built by the Navy itself, at Portsmouth Dockyard. She was laid down on 13 November 1915, launched on 16 December 1916 and completed on 1 June 1917, under Lieutenant Commander John Fenwick Hutchings.

She was a K boat in every respect. She was 339 feet long, steam-driven, with two funnels and oil-fired boilers that gave her twenty-four knots on the surface, fast enough to keep up with the battle fleet, and she had all the problems that came with that.

Before she could dive, the funnels had to be lowered and sealed, the boilers shut down and every opening closed, and the whole procedure took minutes. Once under, a very long boat that went down at the slightest angle could reach her maximum depth astonishingly quickly.

The full story of why the Navy built these extraordinary ships, and what they cost, is told in HMS K3.

K5 was no luckier than her sisters during the war. On one dive control was lost and she drove her bow into the mud of the Firth of Forth. On another occasion, at night in harbour, she was in collision with a destroyer that was being towed.

On 31 July 1918 two of her stokers, Chief Stoker George Booker and Stoker First Class Michael Jordan, were lost overboard and drowned. It was a hard ship to serve in, and her crew changed a great deal, with officers and men coming and going more often than was good for any submarine.

A New Captain

In April 1920 K5 was given a new captain, Lieutenant Commander John Austin Gaimes, and nobody could have accused the Navy of sending her a novice. Gaimes had been a submariner for more than a decade.

He had commanded the little A9 in 1911 and the C37 in 1913, and in the last year of the war he had commanded the minelaying submarine E45 out of Harwich, laying mines deep inside the Heligoland Bight, at the doorstep of the German fleet's bases. By one account he carried out more operations in the North Sea and the Bight in that period than any other submarine officer, and in June 1918 he was awarded the DSO.

The operation that earned it was carried out between 23 and 25 April 1918. The Germans kept swept channels open through their own minefields so that their ships and U-boats could get in and out of the Bight, and they marked them with buoys.

Gaimes was by then the senior submarine officer at Harwich, and according to one account of the operation E45 went in along one of those channels, following the German buoys, and laid his mines in it close to the anti-submarine boom off Heligoland itself, practically in the gateway the U-boats used.

It needed a cool head, accurate navigation and a willingness to spend a long time in the one stretch of water where every German patrol knew exactly where to look. Minelaying submarines rarely saw what their mines did, but these had been laid where the enemy least expected them, which is the whole art of the thing.

He was exactly the man to take an awkward ship in hand. The trouble, as it turned out, was that he had a new crew.

20 January 1921

On 19 January 1921 the fleet sailed from Torbay for Spain, and K5 went with it, in company with the light cruiser Inconstant and a group of K boats that included her sister K15. On the way south, some 120 miles south-west of the Isles of Scilly, the ships split up to take their positions for a mock battle.

K5 signalled that she was diving. It was the last signal anybody received from her. When the exercise ended she did not surface, and the other ships began to search. About an hour before dusk somebody spotted a battery cover from a K boat floating on the water.

The next morning a sailor's ditty box was found, the small wooden box in which a rating kept his letters, photographs and sewing kit. It was the last trace of K5 and of the 57 men aboard her: Gaimes, five other officers and 51 ratings.

What Happened?

Nobody knows. There were no survivors, no wreck was found and no distress signal was heard.

The explanation generally accepted is that something went wrong on the dive, perhaps a valve or a vent left open, perhaps the hydroplanes, perhaps simply a new crew who did not yet know the boat, and that she went down at an angle steep enough to take her past her diving depth of about two hundred feet before she could be stopped. The water there is far deeper than that.

Once a K boat passed her depth her hull would have given way, and the end, at least, would have been very quick.

A retired rear admiral, S. S. Hall, writing in The Times, said that it might be taken as certain that the loss was due to some delay, meaning that something in the long and complicated business of shutting down a steam submarine for diving had not been done in time. Nobody could say what.

The record says simply that she foundered for reasons unknown.

Remembered at Sea

The Navy did not forget her. On its way home from the Mediterranean in 1922 the fleet, led by the battlecruiser HMS Hood, stopped at the position where K5 had gone down, dropped wreaths on the water and held a memorial service. Her crew have no grave but the sea, and their names are on the naval memorials.

K5 was the worst disaster to strike the class since May Island, and she was lost not in war or in a crowded estuary at night but in daylight, in open water, in peacetime, at the hands of an experienced captain. It did a great deal to finish the class.

Five months later K15 sank in Portsmouth Harbour, and within a few years the K boats were gone. The photograph at the top of this page, taken from an aircraft, shows K5 at speed with the smoke from her boilers streaming out across the sea behind her.

It is a picture of what the K boats were meant to be: a submarine that could run like a destroyer. Beneath the waves she was something else entirely.