Description: Wilhelmshaven. This was an interesting and important raid by 177 aircraft - 129 Lancasters, 40 Halifaxes and 8 Stirlings. The Pathfinders found that the Wilhelmshaven area was completely covered by cloud and they had to employ their least reliable marking method, skymarking by parachute flares using H2S. The marking was carried out with great accuracy and the Main Force bombing was very effective. Crews saw through the clouds a huge explosion on the ground, the glow of which lingered for nearly 10 minutes. This was caused by bombs blowing up the naval ammunition depot at Mariensiel to the south of Wilhelmshaven. The resulting explosion devastated an area of nearly 120 acres and caused widespread damage in the naval dockyard and in the town. Much damage was also caused by other bombs. It has not been possible to obtain details of the casualties from Wilhelmshaven. 3 Lancasters lost, 1.7 per cent of the force.
This raid represented the first blind-bombing success for the H2S radar device.
2 Mosquitos to Bochum and Hamborn, 36 aircraft minelaying from La Pallice to the Frisians, 5 OTU sorties. No losses.
Total effort for the night: 220 sorties, 3 aircraft (1.4 per cent) lost.