HMS Tay (K232): Commander Gretton's Frigate at the Turning Point of the Atlantic

Built on Teesside

HMS Tay was built by Smiths Dock Company at South Bank-on-Tees, her keel laid on 10 September 1941, launched on 18 March 1942 and commissioned on 5 August that year, a Group I River-class frigate assigned to convoy escort duty in the Western Approaches and the wider Atlantic.

Joining Commander Gretton's Escort Group

When Commander Peter Gretton took command of Escort Group B7 in December 1942, Tay was one of its core ships, serving alongside the destroyers HMS Duncan and HMS Vidette and the corvettes Alisma, Loosestrife, Pink, Sunflower and Snowflake, a group that would go on to become one of the most celebrated escort formations of the entire Battle of the Atlantic.

Why Keeping the Same Ships Together Mattered

The phrase escort group does a lot of quiet work in that paragraph and is worth unpacking, because permanent groups were one of the genuine reforms of the Atlantic war. For the first two years, escorts were assembled ship by ship for each convoy out of whatever happened to be available, which meant that a destroyer captain frequently found himself in command of four corvettes he had never worked with, whose captains he did not know, using signals and procedures they had not practised together. It is a very poor way to fight at night.

From 1942 the Western Approaches command began keeping groups together permanently instead, training them as units between convoys, and the difference was immediate. B7 under Peter Gretton is the standard example: the same destroyers and corvettes, sailing together month after month, drilled until each captain knew what the others would do without being told. That is what makes a tactic like the search plan possible at all, and it is why one group could destroy six U-boats in a week when the same ships spread across six convoys would have destroyed none. Two of the corvettes are here, HMS Snowflake (K211), whose article carries the full account of ONS 5, and HMS Alisma (K185).

Convoy HX 231

In April 1943, B7 covered Convoy HX 231 as it came under sustained attack from Wolfpack Lowenherz, a brutal engagement in which six merchant ships were lost but two U-boats were destroyed and five more damaged, a costly but ultimately favourable exchange for the escorts.

The Turning Point at ONS 5

The following month, B7 escorted the now-legendary Convoy ONS 5, widely regarded by historians as the turning point of the entire Atlantic campaign.

Though the convoy lost thirteen ships to sustained U-boat attack, the escort group destroyed six U-boats and disabled seven more, at least four of them credited to B7, a battle so decisive that it marked the beginning of the end for Germany's U-boat campaign in the North Atlantic.

The Reservist Who Finished the Battle

There is a name that belongs to this ship and rarely gets attached to her. Gretton was not present for the end of ONS 5. Duncan had been running low on fuel for days, the weather was far too heavy to take any from the tanker sailing with the convoy for exactly that purpose, and on 3 May he had to break off for Newfoundland; he got there at eight knots with four per cent of his fuel left in the tanks, which is about as fine a margin as a destroyer captain ever cuts. Command of the escort passed to the commanding officer of Tay, Lieutenant Commander Robert Sherwood.

Sherwood was a Royal Naval Reserve officer, which is to say a professional merchant seaman rather than a career naval one, and it was under him, over the last three nights, that the escort destroyed most of the U-boats and the battle was won. He was awarded the Distinguished Service Order for it. It is worth stating plainly what that means: the most important convoy battle of the Second World War was fought to a finish by a merchant navy officer commanding from a frigate, after the regular officer in charge had been forced to leave for want of fuel. The Atlantic was won by that sort of man in very large numbers, and the reserve officers are not usually the ones whose names get attached to the victory.

What made it possible to win at all in May, when the same convoys were being torn apart in March, is set out in HMS Swale (K217): eight weeks separate the worst convoy battle of the war from the one that ended the U-boat offensive, and the difference was very long range aircraft, escort groups that could be spared to reinforce, and ships like this one that had finally been given the radar, the weapons and the training to use them.

A Transfer to the Indian Ocean

In June 1943, Tay transferred away from the Atlantic to the Eastern Fleet, spending the rest of the war on operations throughout the Indian Ocean, a considerably quieter theatre than the one in which she had already played her part in two of the most consequential convoy battles of the war.

Scrapped at Rosyth

After the war, Tay remained stationed at Singapore before returning to Britain in 1947, spending nearly a decade in reserve before being placed on the disposal list in 1956. She was towed to the Rosyth breakers on 26 September that year and scrapped just two days later, a quiet end for a ship that had once stood alongside some of the most famous escorts of the Battle of the Atlantic.