of escorting surface ships. All four carriers had participated in the attack on Pearl Harbor at the start of the Pacific War. In addition to the carrier-based aircraft, 54 land-based bombers also struck Darwin in a high-level bombing raid nearly two hours after the first one struck at 0956. These comprised 27 G3M "Nell" bombers flying from Ambon and another 27 G4M "Betty" bombers operating from Kendari in Celebes. Air raids First raid The four Japanese aircraft carriers launched 188 aircraft on the morning of 19 February. The main objective of their crews was attacking ships and port facilities in Darwin Harbour. Their aircraft comprised 81 Nakajima B5N ("Kate") light bombers, 71 Aichi D3A ("Val") dive bombers, and an escort of 36 Mitsubishi A6M ("Zero") fighters. While the B5N was a purpose-built torpedo bomber, it could instead carry up to of bombs and there is no evidence of torpedoes being used on this occasion; the D3A could carry up to of bombs. All of these aircraft were launched by 8.45 am. This wave was led by Commander Mitsuo Fuchida, who had also commanded the first wave of attackers during the raid on Pearl Harbor. On their way to Darwin, Zeros shot down a US Navy PBY Catalina and strafed a USAAF C-47 Skytrain on the ground, near Melville Island. At 9.35 am Father McGrath of the Sacred Heart mission on Bathurst Island, who was also an Australian coastwatcher, sent a message using a pedal radio to the Amalgamated Wireless Postal Radio Station at Darwin that a large number of aircraft were flying overhead and proceeding southward. The message was then relayed to the Royal Australian Air Force Operations at 9.37 am. No general alarm was given until about 10 am as the RAAF officers there wrongly judged that the aircraft which had been sighted were the ten USAAF P-40s, which were returning to Darwin at the time after reports of bad weather forced them to abort a flight to Java via Kupang, West Timor. As a result, the air raid sirens at Darwin were not sounded before the raid. Flying escort in a Zero fighter, Petty Officer Yoshikazu Nagahama was separated from his squadron while he was attacking the PBY flying boat and arrived over the city alone ahead of the strike force, which was making a turn to attack from the south. He engaged five US Army Air Force