Japanese scouts strip the Rabaul raid of surprise

Task Force 11 approached Rabaul without the intended ANZAC reinforcement because that squadron lacked the fuel to accompany it. Lexington's radar found Japanese reconnaissance aircraft while the carrier was still roughly 400 nautical miles from the target and outside its practical strike radius. John Thach led the effort that destroyed two H6K Mavis flying boats, but a third scout reversed course and escaped. The lost scouts and increased radio traffic made it clear that Rabaul knew an American carrier force was nearby. Wilson Brown therefore broke off the mission rather than continue toward an alerted base and a surface interception force. The decision preserved Lexington for later operations while accepting that surprise was the raid's essential protection.