In March 1915, the division was put on warning for overseas service. In early April, the division starting leaving Avonmouth and the last elements landed at Alexandria before the end of the month. By the middle of May, the horse artillery batteries were near Ismaïlia on Suez Canal Defences. On 14 July 1915, B Battery, HAC (along with Berkshire, RHA of II Brigade) left for Aden. They fought a sharp action at Sheikh Othman on 20 July, that removed the Turkish threat to Aden for the rest of the war, before returning to Egypt.