While the Marines were pressing westward from Yŏngsan, Task Force 77 had moved north again into the Yellow Sea. This body of water, from the viewpoint of a carrier force commander, is a somewhat restricted one. As a result of the commanding position of the Shantung Peninsula, no part of the Yellow Sea is more than 200 miles from a Communist shore; above the latitude of Sŏul the operating area, less than 100 miles from Shantung, comes within progressively easier bomber range of the Soviet-occupied Port Arthur Naval Base Area. And for a carrier force dependent on the lee gauge, geography is compounded by meteorology: the prevailing light summer winds, of a mean velocity of six knots and from the northerly semicircle, do nothing to help the commander fight his way out if brought to action.
The approach to this area, therefore, had necessarily been somewhat tentative. Early strikes on North Korea had been launched from south of 37°, and operations against southern targets had been conducted from the waters west of Mokp'o. But the tendency had been northward: on 20 August aircraft had been flown off in about 37°, and now on the night of 3 September Admiral Ewen took his force into the pocket, through the narrows between the Shantung Peninsula and Korea’s western tip, to launch on the morning of the 4th from a position on the 38th parallel against targets in the P'yŏngyang- Chinnamp'o region.