Reinforced on 6 May by Rear Admiral Aubrey W. Fitch's TF 11, Fletcher planned to meet the Japanese in the Coral Sea on 7 May, to stop the enemy thrust toward Port Moresby. On that day, each side attempted to strike blows with carrier aircraft; the Americans enjoying more success in that planes from "Yorktown" and "Lexington" sank . Japanese planes, attempting to strike the Americans, could not find them in the gathering darkness, and a twilight encounter between the returning Japanese air groups and American fighters robbed the enemy of experienced crews as well as virtually irreplaceable aircraft. "Anderson", assigned to the Air Group (TG 17.5), operated in the screen of "Lexington".