HMS Sterlet (N22): Lost in the Skagerrak After Sinking a Gunnery Ship

Laid Down at Chatham

HMS Sterlet was built at Chatham Dockyard, ordered on 2 March 1936, laid down on 14 July 1936, launched on 22 September 1937 and commissioned on 6 April 1938, an S-class submarine that would spend her brief war under the command of Lieutenant Commander Gerard Henry Stacpoole Haward.

Six Patrols in the North Sea

Sterlet completed six war patrols between September 1939 and March 1940, operating chiefly in the North Sea and off Norway, before departing Harwich on 1 April 1940 for her seventh patrol, ordered to watch the western coast of Denmark and the entrance to the Skagerrak, waters that would soon become extremely dangerous as the German invasion of Norway loomed.

The dates are the thing here. She left Harwich on 1 April 1940 and the German invasion of Norway and Denmark began on the 9th. Sterlet was already on station, in the entrance to the Skagerrak, when the largest amphibious operation the Germans had yet attempted came through it. She was not sent to intercept an invasion; she was sent to watch a coast, and the invasion arrived on top of her.

The name, incidentally, is a fish, as the whole class was. A sterlet is a small sturgeon of the Black Sea and the Caspian, prized for its roe, and her Chatham-built cousin HMS Sturgeon carried the name of the same family of fish. There is nothing profound in it. The Royal Navy needed a great many names beginning with S and the fishmonger's slab is as good a place to look as any.

That made the Skagerrak, for a few weeks, the most target-rich and the most lethal water in Europe. Everything the German army needed for Norway had to pass through it, and everything the German navy could scrape together was escorting, patrolling and mining it. The Royal Navy lost submarines there at a rate it would not sustain again until the Mediterranean.

Sinking the Brummer

At 23:06 on 15 April 1940, Sterlet sank the German gunnery training ship Brummer in the Skagerrak, her torpedo striking the bow so effectively that it sheared clean off, a sharp and decisive success. She is also believed to have attacked a German convoy on 18 April, though this action was never officially reported back to base.

What the Brummer Was, and How Long She Took to Die

The target deserves identifying properly. The Brummer was an anti-aircraft gunnery training ship, built to teach German sailors to shoot at aircraft, and she was fitted as a minelayer as well, which was to be her wartime job. In April 1940 she was doing neither: she was acting as command ship of a transport squadron in Operation Weserubung, running the invasion traffic into Norway. Sinking her removed a headquarters as well as a hull.

She also did not go quickly. The torpedo took her entire bow section off, which is spectacular damage, but the rest of the ship stayed afloat for something like nine hours before finally capsizing. That is the difference between a decisive hit and a massacre: her people had most of a night to get clear, and most of them did.

British and German accounts differ by a day on when it happened, the Royal Navy record putting the attack at six minutes past eleven on the night of 15 April and German sources dating it to the 14th with the capsize early on the 15th. It is not the sort of discrepancy anybody is going to settle now, and it is worth noting rather than quietly choosing one.

The Germans replaced her almost at once, and in the most direct way available. They had just captured the Norwegian minelayer Olav Tryggvason at Horten during the invasion, and on 16 April, a day or so after the first Brummer went down, they renamed her Brummer. The name was back in the fleet list before the wreck had settled.

Lost Without Trace

HMS Sterlet's last confirmed signal, reporting an unsuccessful attack on a convoy of three merchant ships and a destroyer west of the Skaw, was received on 12 April 1940, and she is believed to have been sunk on or around 18 April 1940 in the Skagerrak south of Larvik, Norway, most likely by the German anti-submarine trawlers UJ 125, UJ 126 and UJ 128, though a mine cannot be ruled out as an alternative cause.

There is an apparent contradiction in that account worth clearing up, because it looks like an error and is not. Her last confirmed signal was on 12 April. She sank the Brummer on the 15th and possibly attacked a convoy on the 18th. Both of those are after the last time anybody heard from her.

That is because a submarine on patrol does not report as she goes. Transmitting is how you are found, and in the Skagerrak in April 1940 it was close to suicidal, so she said nothing and got on with it. The Brummer was credited to Sterlet after the war, from German records, by matching a time and a position to the only British boat that could have been there. Her greatest success was established by the enemy's paperwork, years after everyone aboard was dead.

Her entire crew was lost, their exact fate never conclusively established, a quiet and uncertain end for a submarine that had just delivered one of the sharper blows of the young war.

Forty men were lost with her, and she was posted overdue on 27 April 1940. Her commanding officer, Lieutenant Commander Gerard Haward, had taken her through all seven patrols. She had been in commission for two years and at war for seven months.

She was not remotely alone. April 1940 off Norway cost the Royal Navy three submarines in nine days: HMS Thistle was torpedoed by the German submarine U-4 on the 10th, HMS Tarpon was lost on the 14th, and Sterlet on the 18th. HMS Seal was mined and captured in the same waters a fortnight later. That is what the Skagerrak and its approaches were doing to the submarine service that spring.

It was of a piece with the whole first year. HMS Seahorse and HMS Starfish had both gone from the Heligoland Bight in January, HMS Snapper would be lost the following year, and of the four Chatham-built boats of the first S-class group only HMS Sturgeon came through the war at all. Britain fought that opening year in shallow, narrow, heavily patrolled seas, and it cost the submarine service more than any comparable period afterwards.

Nobody knows how she died. The three trawlers are the likeliest answer, a mine is entirely possible, and no wreck has been identified. What is certain is a gunnery training ship on the bottom of the Skagerrak with her bow lying separately nearby, and forty men who were never told that the attack had worked.