744 Naval Air Squadron is a Naval Air Squadron of the Royal Navy's Fleet Air Arm. It was initially active in 1943, based in Nova Scotia. A second 744 NAS was formed, in early 1944, in Northern Ireland, for Merchant Aircraft Carrier training, meaning the first iteration was re-designated 754 NAS. The squadron's primary focus turned to Anti-submarine warfare training, which then further developed into trialing new submarine detection technology, ending in 1956. In 2018 it reformed as the Mission Systems and Armament Test and Evaluation Squadron.