It was defended by heavy 15-inch naval guns stationed at Fort Siloso, Fort Canning, and Labrador, as well as the Royal Air Force airfields at RAF Tengah & RAF Sembawang.
It was defended by heavy 15-inch naval guns stationed at Johore battery, Changi, and at Buona Vista. Air defense relied in the Royal Air Force airfields at RAF Tengah & RAF Sembawang.