The Avenger T1, based on the Beech King Air 350ER twin-turboprop, is the newest fixed-wing aircraft type to enter Royal Navy service. Four examples are operated by 750 Naval Air Squadron at Royal Naval Air Station Culdrose in Cornwall, the fleet being provided to the Navy under a contract with industry partner Ascent Flight Training. The Avenger's role is to train observers for the Navy's maritime helicopter force, instructing them in the various systems and the management of sensor equipment. 750 NAS, which previously operated the Jetstream, began training on the Avenger in September 2012. It has a mixture of military and civilian instructors.