Escort Group B7

Escort Group B7 was a British formation of the Royal Navy which saw action during the Second World War; principally in the Battle of the Atlantic.

Formation
Escort Group B7 was one of seven such British naval groups which served with the Mid-Ocean Escort Force (MOEF). It provided convoy protection in the most dangerous middle section of the North Atlantic route. The MOEF was originally to be five American, five British and four Canadian groups. B7 was formed in the spring of 1942, following the inability of the USN to form groups A-4 and A-5 due to other commitments. To replace them, two new escort groups, Escort Group B6 and Escort Group B7, were formed.

Service history
Led by HMS Firedrake (H79), under the leadership of Commander William Banks, B7 comprised six Flower-class corvettes; HMS Loosestrife (K105) from the disbanded American group A-5 and HMS Alisma (K185), HMS Coreopsis (K32), HMS Jonquil (K68), HMS Pink (K137) and HMS Sunflower (K41). These were joined later by the destroyers HMS Chesterfield and Ripley.

B7's first convoys, in the spring of 1942, were uneventful and as the Battle of the Atlantic increased in intensity in the summer and autumn, the group's charges were escorted without loss. In December, while escorting Convoy ON 153, the convoy came under attack and three ships were sunk. During this action, on 11 December, Firedrake was torpedoed by the U-boat GS U-211 and sank with the loss of 168 of her crew, including her commander and the group's Senior Officer – Escort (SOE), Commander Eric Tilden. Thirty-five survived the torpedoing but only 27 managed to get on board Sunflower (Captain John Treasure Jones).

B7's new SOE was Commander Peter Gretton, of HMS Duncan (D99), a tough and capable leader, who quickly molded the group to his own image. At this point B7 comprised the destroyer Duncan, HMS Vidette (D48), the frigate HMS Tay (K232) and the corvettes HMS Alisma, Loosestrife, Pink, Sunflower and HMS Snowflake (K211).

After several convoys had been escorted without loss, B7 covered Convoy HX 231 in April 1943. This came under attack by Wolfpack Lowenherz, which sank six ships, for the loss of two submarines destroyed and five damaged. In May 1943, B7 escorted Convoy ONS 5, sometimes regarded as the turning point of the Atlantic campaign. In a week long battle against wolfpacks, Star, Amstel and later Fink, Convoy ONS 5 lost 13 ships, for the destruction of six U-boats, and the disabling of seven. At least four of these were credited to ships of B7. Later that month, returning with Convoy SC 130, B7 saw the destruction of between three and five U-boats (sources vary) for no losses. at least one of these was credited to ships of B7. A series of uneventful convoys followed, as the U-boat Arm withdrew from the North Atlantic after Black May, while Gretton lobbied for a chance for B7 to operate as a Support Group. In October 1943 this was given, as the German U-boat arm launched its autumn offensive.

B7 was involved in the battles for convoys ONS 20 and ON 206, Convoy ON 207 and Convoy ON 208, during which nine U-boats were destroyed. The battle for Convoy ONS20/206 saw six U-boats sunk, of which GS U-631 was credited to Sunflower and GS U-844 was damaged by Duncan, to be destroyed later in an air attack. Convoy ON 207 saw three U-boats destroyed, GS U-282 by ships of B7, another shared with aircraft. B7 had steamed 6700 nmi, crossing the Atlantic five times. The group members had refuelled at sea on six occasions and had re-armed with depth charges at sea.

B7 returned to escort duty on the North Atlantic route, continuing without major incident until the group was disbanded in the summer of 1944 as part of the preparations for Operation Neptune, the naval contribution to the Normandy invasion.

Ships lost

 * Firedrake was torpedoed and sunk by U-211 when escorting Convoy ON 153 on 16 December 1942.

U-boats destroyed
Source:
 * U-192 depth-charged by Pink on 5 May 1943.
 * U-638 depth-charged by Loosestrife on 5/6 May 1943.
 * U-125 rammed by HMS Oribi and finished off with gun-fire by Snowflake on 6 May 1943.
 * U-531 depth-charged by Snowflake and hit by Hedgehog mortar from Vidette on 6 May 1943.
 * U-381 depth-charged by Snowflake and hit by Hedgehog from Duncan on 19 May 1943.
 * U-631 depth-charged by Sunflower on 17 October 1943.
 * U-274 attacked by aircraft, hit by Hedgehog from Duncan on 26 October 1943.
 * U-282 by Duncan and Vidette on 29 October 1943.