After the immediate postwar return of American aircraft, Cold War alliance needs brought Avengers back into British use while the home-grown Gannet was completed. The Gannet then provided medium- and long-range anti-submarine search beyond the helicopters' inner zone. Fixed-wing reach was especially valuable against submarines that had to surface or snorkel, but nuclear boats still depended on some contact with the outside world. A patrol aircraft did not need to detect and kill a submarine on every sortie to matter. Its presence forced submarines to account for possible detection, discouraged concentrated attacks, and narrowed the enemy's operational choices. The effect resembled fighters breaking up an incoming air strike even when the interception destroyed few aircraft. Long-range ASW was therefore an operational deterrent during conflict as well as a peacetime search capability.
Chapter · 43:34-49:37
Gannet patrols made long-range ASW a form of operational deterrence
Avengers and Gannets extended carrier ASW beyond helicopter range, forcing submarines to disperse and alter attacks even when patrol aircraft found no target.