Imperial Japanese Navy Lieutenant Michio Kobayashi before the Battle of Midway. Kobayashi flew a D3A1 type 99 dive bomber (Allied code name "Val") from IJN Hiryu as the commander of her Kanjo Bakugekikitai (bombing squadron) during the successful attack on USS Yorktown (CV-5) on June 4, 1942. He piloted plane number lying BII-201, with his gunner along, Warrant Officer Ono Yoshinori. After the destruction of IJN Akagi, IJN Kaga and IJN Soryu at 1022, Kobayashi led eighteen dive bombers against Task Force 17 built around Yorktown. The Americans' Combat Air Patrol of Grumman F4F-4 Wildcat fighters did not all receive the radio call for help from Yorktown and only six fighters engaged at 1155. Since the D3A1s lacked adequate fighter cover (the four Zeroes had pulled away after returning Douglas SBD Dauntlesses) Kobayashi jettisoned his bomb and engaged the Wildcats. Meanwhile, his flight braved the heavy antiaircraft fire and scored three hits with armor-piercing 551-pound (250-kilogram) bombs. Yorktown lost her boilers and stopped dead in the water. Yorktown had many casualties and made emergency repairs that were so effective that a B5N2 torpedo bomber (allied code name "Kate") attack later in the day reported that it was a different carrier. Out of twenty-two attacking planes, thirteen dive bombers and three fighters were destroyed. Kobayashi, circling the engagement and reporting via radio, was shot down by Wildcats from Enterprise's Fighting Six (VF-6) flown by Lieutenant (Junior Grade) Thomas C. Provost III and Ensign James A. Halford, Junior.