The British HACS and FKS anti-aircraft fire control systems were less than satisfactory in service during World War II. While Delhi was in refit the British asked that the U.S. Navy's MK 37 Gun Fire Control System be installed as a test bed along with the 5-inch/38 calibre guns. The results were most impressive to the service and a request was issued for 42 of the systems to be sent to the Royal Navy for installation on their ships.
During World War II, British anti-aircraft fire control systems were unsatisfactory in service. While Delhi was undergoing refit, the British requested that the U.S. Navy's MK 37 Gun Fire Control System be installed alongside the 5-inch/38 calibre guns as a test bed. The results were highly commendable to the service and a request was made for 42 of these systems to be sent to the Royal Navy for installation on their ships.