Day 400 October 4, 1940

Battle of Britain Day 87. Rain and mist again cause poor visibility over Southern England and Luftwaffe sends a steady stream of reconnaissance flights and single bomber raids with peak intensity around 3 PM. Bombs are dropped in Kent and near London hitting mainly homes, farms and few factories. 2 Ju88 bombers are shot down for the loss of 3 RAF fighters (1 pilot killed). There is widespread bombing on a small scale overnight but London is heavily bombed between 7 and 9 PM.

Operation Lucid. Fire ships (tankers War Nizam & War African filled with 50% heavy fuel oil, 25% diesel oil and 25% petrol) depart Sheerness and Harwich escorted by 11 destroyers, 6 minesweepers and torpedo boats. However, rough seas force the operation to be cancelled.

General Charles de Gaulle arrives in Douala, French Cameroon (which is sympathetic to the Free French) on board British cruiser HMS Devonshire, to organize the invasion of neighbouring Gabon (loyal to Vichy France). After the failed invasion of French West Africa at Dakar, de Gaulle is keen rally support for the Free French cause in Equatorial Africa, to mount operations from Chad into Italian-held Libya and to deny Germany use of the Atlantic coast for basing submarines and surface raiders to disrupt Allied shipping around Africa.

British submarine HMS Rainbow collides with Italian steamer Antonietta Costa and sinks in the Adriatic Sea, 20 miles North of Brindisi, Southern Italy (all 55 hands lost). Submarine HMS Triton shells shore installations at Vado Ligure and Savona, near Genoa, Northern Italy. Triton also sinks Italian steamer Franca Fassio 20 miles to Southwest of Savona, in the Ligurian Sea. Submarine HMS Tetrarch attacks another Italian merchant ship nearby, without success.