Exercise OC linked submarine shadowing with air and ASW screens

OC used L-class submarines to represent a G-class flotilla operating from Philippeville. Intelligence about a damaged battlecruiser drew the opposing fleet to sea, giving the submarines an opportunity to form an interception line. Their orders were to locate, shadow, and report the fleet so Red could bring it to action rather than merely attack whatever appeared first. Courageous and its attendant destroyers operated with the battle squadron, making air cooperation and carrier positioning part of the same reconnaissance problem. Submarines served as fleet scouts and information providers alongside their role as torpedo attackers.