On the 8th December 1941, Japanese forces landed in northern Malaya, and HMS Prince of Wales, HMS Repulse and four destroyers were sent to attack the invasion force. After finding no targets the British ships were returning to Singapore when, late in the morning of the 10th December, they were attacked by Japanese high-level bombers and torpedo planes. With no air cover to protect them, both ships were hit several times. Repulse sank at about 12:30 hours. Prince of Wales capsized and followed Repulse to the bottom less than an hour later. Signalman McCullagh was one of the 327 men out of a total the crew of 1612 of the Prince of Wales who were reported as missing presumed killed. He is commemorated on the Plymouth Naval Memorial, Panel 50, Column 2. With its central position on the Hoe overlooking Plymouth Sound in Devon, the Plymouth Naval Memorial is a well-known local landmark. The memorial commemorates more than 7,200 naval personnel of the First World War and nearly 16,000 of the Second World War who were lost or buried at sea.