Beatty's argument about Eagle's air defence had two distinct parts. Fighters could intercept and disrupt an incoming raid before it reached the ship, making them the carrier's strongest outer defensive layer. The carrier still needed a close-range answer when aircraft penetrated the fighter screen. At 22,200 tons standard displacement, Eagle could carry both fighters and a modest battery of 4-inch guns without accepting the far heavier cruiser-style weapons proposed elsewhere in her design. The result was layered carrier defence: aircraft extended protection outward, while guns defended the final approach.
Notable Point · 10:36-12:17
Why a carrier needed both fighters and anti-aircraft guns
Beatty was right that fighters formed a carrier's best outer air-defence layer, but that did not justify reducing the ship's own anti-aircraft battery.