Illustrious was the first of Admiral Reginald Henderson's armoured-hangar fleet carriers, designed to operate with the battlefleet and maintain a sustained rate of flying. At Taranto, however, the immediate problem was the limited room over the Mar Grande and Mar Piccolo. A large concentration of torpedo aircraft would have competed for the same attack lanes and risked collision or friendly flak exposure. Dividing the strike let aircraft make their runs through the harbour with more space and flexibility.
Notable Point · 5:58-7:16
Why Illustrious sent spaced strike waves
HMS Illustrious was built for fleet operations, but Taranto's confined harbour made two manageable waves safer than one congested mass of aircraft.