targets in and near Shanghai. The Japanese fighters had their first aerial engagement on 22 August when four A4Ns surprised 18 Nationalist Curtiss Hawk III fighters and claimed to have shot down six without loss. The following day, four A4Ns claimed to have shot down nine Chinese fighters without loss to themselves. The carriers returned to Sasebo at the beginning of September to resupply before arriving off the South China coast on 21 September to attack Chinese forces near Canton. Nine fighters from Ryūjō escorted a raid on the city and claimed six of the defending fighters. While escorting another raid later that day, the Japanese pilots claimed five aircraft shot down and one probably shot down. The dive bombers attacked targets near Canton until the ship sailed to the Shanghai area on 3 October. Her air group was flown ashore on 6 October to support Japanese forces near Shanghai and Nanking. Ryūjō returned home in November and briefly became a training ship before she was assigned to Rear Admiral Tomoshige Samejima's Second Carrier Division. In February 1938 the ship replaced her A4N biplanes with nine Mitsubishi A5M "Claude" monoplane fighters. The division supported Japanese operations in Southern China in March–April and again in October. Captain Kiichi Hasegawa assumed command on 15 November 1939. Ryūjō was given a refit that lasted from December 1939 through January 1940 and became a training ship until November when she became the flagship of Rear Admiral Kakuji Kakuta's Third Carrier Division. Hasegawa was relieved by Captain Ushie Sugimoto on 21 June. The ship's air group then consisted of 18 Nakajima B5N torpedo bombers and 16 A5M4 fighters. When the First Air Fleet was formed on 10 April 1941, Ryūjō became flagship of the Fourth Carrier Division. World War II The ship's assignment at the beginning of the Pacific War was to support the invasion of the Philippines, initially by attacking the American naval base at Davao, Mindanao, on the morning of 8 December. Her air group had not changed, but four of each type of aircraft were spares. Ryūjōs initial airstrike consisted of 13 B5Ns escorted by nine A5Ms with a smaller airstrike later in the day by two B5Ns and three A5Ms. They accomplished little, destroying two Consolidated PBY seaplanes on the ground for the loss of one B5N and one A5M. The ship covered the landing at Davao on 20 December and