Escort Group B7

Escort Group B7 was a British Royal Navy formation created in the spring of 1942 for service with the Mid-Ocean Escort Force during the Battle of the Atlantic. It was one of seven British escort groups assigned to protect Allied convoys across the central North Atlantic, the section of the route where merchant ships were particularly vulnerable to German U-boat attacks. The group was established after the United States Navy was unable to form two planned escort groups, A-4 and A-5, because of other operational commitments. Britain responded by creating Escort Groups B6 and B7. B7 initially operated under Commander William Banks, with HMS Firedrake serving as its principal leadership ship. Its original composition centered on six Flower-class corvettes: Alisma, Coreopsis, Jonquil, Loosestrife, Pink and Sunflower. Loosestrife had previously been associated with the disbanded American escort group A-5. The group was later reinforced or reorganized with larger warships, including the destroyers Chesterfield and Ripley. Its early convoy assignments in the spring and summer of 1942 passed without major loss, but the group entered a much more dangerous phase late that year. While escorting Convoy ON 153 in December 1942, B7 came under attack by German submarines. HMS Firedrake was torpedoed by U-211 and sank on 16 December, with the loss of 168 men, including Commander Eric Tilden, who had become the group's senior officer for escort. Thirty-five men survived the sinking, although only 27 reached HMS Sunflower. The loss forced a major change in the group's leadership and composition. Commander Peter Gretton subsequently became senior officer for escort, and B7 included destroyers Duncan and Vidette, frigate Tay, and corvettes Alisma, Loosestrife, Pink, Sunflower and Snowflake. Under Gretton, B7 developed a more aggressive and tactically capable reputation. It escorted Convoy HX 231 in April 1943, during a battle in which six merchant ships were sunk while two U-boats were destroyed and five damaged. In May, B7 participated in the escort of Convoy ONS 5, one of the most consequential convoy battles of the Atlantic campaign. The convoy lost 13 ships during a week of attacks, but Allied escorts and aircraft destroyed six U-boats and disabled seven; B7 was credited with at least four of the U-boat successes according to the referenced account. Later that month, while escorting Convoy SC 130, the group helped counter another major submarine attack. Between three and five U-boats were destroyed in the wider action, with no loss to the convoy escort group, and at least one destruction was credited to B7. After the German U-boat force temporarily withdrew from the North Atlantic following the strategic reversal known as Black May, Commander Gretton pressed for B7 to be used as a mobile support group rather than solely as a conventional convoy escort. That role was approved in October 1943 during a renewed German submarine offensive. B7 then took part in the battles around Convoys ONS 20 and ON 206, ON 207 and ON 208. The actions resulted in the destruction of nine U-boats across the convoy battles. B7 was credited with several successes, including U-631, sunk by Sunflower, and U-282, destroyed by B7 ships. Duncan damaged U-844, which was later destroyed by aircraft. During this period B7 reportedly steamed approximately 6,700 nautical miles, crossed the Atlantic five times, refuelled at sea six times and replenished depth charges at sea. It subsequently returned to routine North Atlantic escort work. The group was disbanded in the summer of 1944 as the Royal Navy reorganized forces for Operation Neptune, the naval phase of the Normandy invasion. B7 was therefore not a commercial brand or continuing organization, but a wartime military unit whose historical significance rests on its role in protecting transatlantic shipping and contributing to the defeat of the German U-boat campaign.

Escort Group B7 was formed by the British Royal Navy in the spring of 1942 as part of the Mid-Ocean Escort Force, an Allied system intended to protect merchant convoys crossing the Atlantic. The formation of B7 followed the inability of the United States Navy to establish planned escort groups A-4 and A-5. Britain created B6 and B7 as replacements, allowing the convoy-protection structure to cover the central Atlantic route. The group first operated with HMS Firedrake and six Flower-class corvettes: Alisma, Coreopsis, Jonquil, Loosestrife, Pink and Sunflower. Commander William Banks led the group during its initial period. The early convoys of spring and summer 1942 were completed without reported loss, but the escalation of German U-boat operations brought B7 into sustained combat later in the year. The group's most serious early loss occurred during the escort of Convoy ON 153 in December 1942. HMS Firedrake was torpedoed by the German submarine U-211 and sank on 16 December. The sinking killed 168 members of the ship's company, including Commander Eric Tilden, the group's senior officer for escort. Thirty-five men survived, and 27 reached HMS Sunflower. This event marked a decisive leadership transition for B7. Commander Peter Gretton took over as senior officer for escort and reorganized the group around a mixture of destroyers, a frigate and corvettes. The later force included Duncan and Vidette, HMS Tay, and the corvettes Alisma, Loosestrife, Pink, Sunflower and Snowflake. Gretton advocated a more assertive anti-submarine role and sought permission for B7 to operate as a support group capable of reinforcing threatened convoy battles. B7 escorted Convoy HX 231 in April 1943. The convoy lost six merchant ships, while Allied forces destroyed two U-boats and damaged five. In May, B7 participated in the escort of ONS 5, a battle frequently treated as a turning point in the Atlantic campaign. The convoy suffered heavy losses, but the German submarine force also suffered severe attrition. Six U-boats were destroyed and seven damaged in the wider battle, with several successes credited to B7. During the return escort of Convoy SC 130 later in May, B7 again operated against German submarines. The action resulted in the destruction of several U-boats without loss to B7's escort force. After the German navy's North Atlantic offensive weakened during the period known as Black May, B7 returned to regular convoy duty while its commander continued to seek a more flexible support-group mission. That request was approved in October 1943 during a renewed German offensive. B7 took part in operations associated with ONS 20 and ON 206, ON 207 and ON 208. Across these convoy battles, nine U-boats were destroyed. B7 was credited with the destruction of U-631 by Sunflower and U-282 by B7 ships; Duncan also damaged U-844, which was subsequently destroyed by aircraft. The group covered roughly 6,700 nautical miles, crossed the Atlantic five times and conducted multiple at-sea refuelling and depth-charge replenishment operations. B7 later resumed North Atlantic escort work without another comparable episode of loss. It was disbanded in the summer of 1944 as naval resources were reorganized for Operation Neptune, the seaborne phase of the Allied invasion of Normandy. Its existence was consequently limited to the wartime convoy campaign, and it left no continuing corporate or commercial successor.

• 1944

  Disbandment

  [1]Escort Group B7en.wikipedia.org

  B7 was disbanded in the summer of 1944 during preparations for Operation Neptune and the Normandy landings.

• 1943

  Escort of Convoy HX 231

  [1]Escort Group B7en.wikipedia.org

  B7 participated in the defense of HX 231 during a major U-boat attack in which six merchant ships were sunk and German submarines were destroyed or damaged.

• 1943

  Participation in ONS 5 and SC 130

  [1]Escort Group B7en.wikipedia.org

  B7 took part in two major May convoy battles associated with the Allied strategic reversal against the U-boat campaign.

• 1943

  Conversion to support-group operations

  [1]Escort Group B7en.wikipedia.org

  In October, B7 was authorized to operate as a support group during the German autumn U-boat offensive.

• 1942

  Formation of Escort Group B7

  [1]Escort Group B7en.wikipedia.org

  B7 was established in the spring of 1942 as a British replacement within the Mid-Ocean Escort Force after planned American groups A-4 and A-5 could not be formed.

• 1942

  Initial North Atlantic convoy service

  [1]Escort Group B7en.wikipedia.org

  The group began escorting convoys across the central North Atlantic with HMS Firedrake and a group of Flower-class corvettes.

• 1942

  Loss of HMS Firedrake

  [1]Escort Group B7en.wikipedia.org

  HMS Firedrake was torpedoed by U-211 while escorting Convoy ON 153, killing 168 people including senior officer Eric Tilden.

A wartime Royal Navy convoy-protection formation specializing in mid-ocean escort operations, anti-submarine warfare and support of Allied shipping across the North Atlantic.

• 1943Convoy HX 231

  North Atlantic

  B7 helped escort HX 231 during a large-scale German submarine attack.

  Outcome. Six merchant ships were sunk; two U-boats were destroyed and five damaged in the wider action.

  Source
• 1943Convoy ONS 5

  North Atlantic

  B7 participated in the week-long defense of ONS 5 against several German wolfpacks.

  Outcome. The convoy lost 13 ships, while six U-boats were destroyed and seven disabled across the battle; at least four successes were credited to B7.

  Source
• 1943Support-group convoy battles

  North Atlantic

  After receiving support-group authorization, B7 operated in the battles involving ONS 20 and ON 206, ON 207 and ON 208.

  Outcome. Nine U-boats were destroyed in the associated convoy battles, with several losses credited wholly or partly to B7 ships.

  Source
• 1942Mid-Ocean Escort Force convoy operations

  North Atlantic

  B7 protected Allied merchant convoys through the central Atlantic, initially completing several assignments without loss before entering heavier combat in late 1942.

  Outcome. The group continued operational service despite the loss of HMS Firedrake during Convoy ON 153.

  Source

• 1943

  Adoption of a support-group roleStrategy

  Background

  Commander Peter Gretton argued that B7 should be able to reinforce threatened convoys and actively hunt submarines rather than remain limited to routine escort assignments.

  Action taken

  The group was authorized in October 1943 to operate as a support group during the renewed German U-boat offensive.

  Aftermath

  B7 participated in several major autumn convoy battles and was credited with multiple U-boat successes before returning to regular escort work.

  Source

1. 1Escort Group B7en.wikipedia.org
2. 2HMS Firedrakenaval-history.net
3. 3HMS Duncannaval-history.net
4. 4Allied warship information: HMS Alismauboat.net