Biscay had been a happy hunting ground for U-boats due to the shipping lanes to Mediterrean and Africa. Although Bomber Command attacked submarine pens on the French coast, this effort proved to be far from highly effective. A constant umbrella of guards to the convoys to the New World had to become a priority, because only a tiny fraction of the Coastal Command aircraft of a range beyond 500 miles available was. The entry of the USA into WWII resulted in detachment of numerous U-boats to the western regions of the Atlantic to prey on shipping near American coast. This relief was only temporal, but enabled Coastal Command to concentrate on scouring as the Northern transit stretch of the North Sea through which all brand new U-boats got into the Atlantic as the Bay of Biscay. On June 4, 1942 four of the only five available Wellington bombers equipped with an ASV radar set combined with Leigh Light were sent over Biscay. Three of them contacted fishing boats in the dark, but the fourth one illuminated two submarines by its searchlight-type beam of light, damaging one of them. It was sunk three days later by a No 10 Sqn´s Sunderland, RAAF. The first positive Leigh Light kill was scored on July 5 – U 512.
That reason for the Czechoslovak No 311 Sqn was ordered to purge all the fishing boats out of the Biscay mid June 1942. Some of the fishing boats proved to be early warning picket ones. First, No 311 Sqn´s crews were tasked to note down the course, crews and identification of all these vessels, often approaching closely. After a week the first leaflets warning these boats against entering the waters of the Bay of Biscay or sunk were dropped . Ten days later an order to sink all of them was issued. Knowledgable of some French manning these vessels under a German command, the No 311 Sqn`s members fired at the sails on their first strafing run. During two weeks the Bay was clear of the fishing boats. If made sightings of some more, they must have been German boats and were sunk mercilessly. Hunting of U-boats ensued. The reaction of Luftwaffe was instant. The number of German twin-engined long range Ju 88 fighters sent together over Biscay was increased to three or even seven.
Wimpy´s Brownings of .303 cal were outgunned and outranged by a Ju 88´s cannon and machine guns. Outnumbered by Ju 88s, No 311 Sqn´s Wellington aircraft DV 665 fell victim to them on Aug 18, 1942. All hands lost. Six days before this loss, the aircraft piloted by Sgt Vaclav Sponar attacked an U boat. The raid was a matter of luck and took twenty seconds. Suddenly out of the cloud base, the crew spotted the submarine at the angle of sixty degrees and went for a bombing run instantly. As the U boat submerged, depth charges dropping were. An oil slick and air bubbles were observed by the crew circling for twenty minutes, but no debris came to surface. The crew were invited to the Coastal Command HQ Northwood, Middlessex and were told no further radio message had been reported from this U boat since their attack. The ´Death in all the Seas´ book by Paul Herbert Freyer gives no U boat was sunk on Aug 12, 1942. Combing the Bay of Biscay without an ASV detection radar set was very often eventless, but cover of Biscay by the RAF aircraft brought the dividends. In 1940 and 1941 only one U boat was sunk there each year , but on Jul 5 U 502, Aug 9 U 578, on Sep 3 U 705, in Sep 1942 U 165 and on Oct 9 U 171 were sent to the sea bottom by the RAF bombers.
The No 311 Sqn´s HD892 aircraft was lost on Sep 15, 1942. No member of No 311 Sqn was made POW on operations for Coastal Command and being overdue meant death in all the cases except one. On Sep 29, 1942 a No 311 Sqn´s HF 921 Wellington bomber was downed by four Ju 88s near the Isles of Scilly while returning to the base. Five men in dinghy were saved. Not only U boats and the vessels sailing in Biscay were the targets of No 311 Sqn. In September three crews lead by P/O Frantisek Bulis were tasked to bomb a warehouse and a blockade runner laying at anchor at the port of Bordeaux having brought india rubber from the Far East on the same day. Both the targets were hit and all the crewmen escaped unhurt.
Bibliography :
Miloslav Vild Fate was my Friend Nase vojsko Publ 1985
Paul Herbert Fryer Der Tod auf allen Meeren Nase vojsko Publ 1982
Chaz Bowyer History of the RAF Dolphin Publ 1977