The aircraft operated by the MSFU were converted Mk1 Hawker Hurricanes that were near the end of their useful lives and were often Battle of Britain veterans.
[2] The MSFU was formed at Speke on 5 May 1941 and provided detachments to the CAM ships, each vessel being equipped with one Sea Hurricane plus an RAF pilot and support crew.
[3] The single catapult consisted of an eighty-five-foot rail, along which a trolley carrying a Hurricane (later Hurricats were used for this) would be propelled by a battery of three-inch rockets over a distance of sixty feet.
Using thirty-degree wing flaps, a pilot could make a successful takeoff while losing minimal height.
CAM fighters were credited with seven kills and their presence was rumoured to discourage the Focke-Wulf Fw 200 Condor aircraft from pressing home attacks on convoys.