26th January 1943
A very active day after a few days of unnerving quiet. KM submarines reported engaging two large enemy transports approaching Dobo. SS 0-21 attacked two ships, scoring four torpedo hits sending one large transport of around 8,000 tons to the bottom of the sea. Aerial recon later in the day spotted small craft fishing survivors out of the water. Indications are that the 0-21 has thwarted an attempt to reinforce or garrison this base.
Forewarning of the Japanese moves had come from Intelligence intercepts of radio messages. For the past week and half regular updates from a unit enroute to Dobo had been monitored, as such the 0-21 was vectored to the base. Furthermore a small flotilla of 3 destroyers has also been ordered to sweep the approaches to Dobo at high speed on the morrow.
The day was also full of action over Merauke and Horn Island as the Japanese belatedly start to react to the landing at the former base. Three raids were intercepted over both bases. 18 enemy planes were reported shot down, but at a cost of 12 of our own fighters. Three ships were also sunk by torpedo carrying betties and one struck a mine at Horn Island. An enemy submarine must have laid this field at some point overnight. The 2750 ton Australian merchant ship Koomilya went down after striking a mine in the early hours of the 26th.