On July 19, Air Group Seven's aircraft bombed Choshin No. 3, scoring five hits on its transformer yard, while Air Group Nineteen aboard "Princeton" bombed Choshin No. 1, and again on July 20, noting a significant increase in AAA defenses. On July 23, the thermo-electric plant at Wonsan was attacked for the first time, by aircraft from "Bon Homme Richard", which reported it completely destroyed. On the nights of July 19–20, and July 21–22, 44 B-29 sorties were flown against Choshin No. 2.