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Sort of #OTD, on the night of 7/8 April 1917, four of the Royal Navy’s small Coastal Motor Boats scored their first success again the Imperial German Navy’s Flanders Flotilla. Late that night, CMBs 4, 5, 6 & 9 sailed from Dunkirk and up towards Zeebrugge. 
IWM Q 57711 1/5
IWM Q 57711 1/5
The RN had observed that during their bombing raids on the harbour, German destroyers tended to sail out beyond the mole until the raid had passed. Tonight, another air raid was conducted in the hope the enemy would do the same.
At 11.30pm, the CMB flotilla commander, Lieutenant Beckett in CMB 4, spotted two German destroyers. All four CMBs launched their torpedoes, a slightly hair-raising affair as the torpedoes launched from the stern. 
IWM 566
IWM 566
At least one of the torpedoes found its mark and destroyer G88 was sunk. It took some time for the Imperial German Navy to establish what had happened: CMBs were relatively new & had been kept under wraps by the RN so initially a bomb or a submarine was suspected. Bundesarchiv
Bundesarchiv
No-one was certain whose torpedo had made the kill, so all four crews received prize money. An additional bonus came from the Germans themselves, who stopped sending destroyers out of the harbour during air raids, subjecting them instead to British bombers. IWM Q 12192 5/5
IWM Q 12192 5/5
