4 EUSAK Front Lines, January 1951 23 5 Pohang Guerrilla Hunt 43 6 Operation KILLER 61 7 Area Gained, February-March 1951 77 8 Operation RIPPER Plan 82 9 Operation RIPPER Zone 87 10 CCF Offensive, April 1951 110 11 Actions of 1/1 and 3/1, April 1951 112 12 Night of 16–17 May 1951 124 13 Drive to Yangu, May 1951 129 14 X Corps Routes of Advance, May-June 1951 139 15 1st Marine Division Zone of Action, June-July 1951 140 16 1st MAW Operating Area, May-July 1951 145 17 1st Marine Division Area, September 1951 174 18 X Corps Zone of Action, September 1951 177 19 EUSAK Dispositions, September 1951 200 20 1st Marine Division Situation, September 1951 205 21 HMR-161 Operations 1951 209 22 EUSAK Dispositions, March 1952 252 CHAPTER I Interlude at Masan _Return to the Bean Patch--1st Marine Division in_ EUSAK _Reserve--General Ridgway New_ EUSAK _Commander--Ridgway’s Declaration of Faith--Marine Personnel and Equipment Shortages--Marine Air Squadrons in Action--The Air Force System of Control--X Corps Conference at Kyongju_ A new chapter in Korean operations began for the 1st Marine Division at 1800 on 16 December 1950 with the opening of the CP at Masan. By the following afternoon all units of the Division had arrived from Hungnam with the exception of VMO-6 and small groups of such specialists as the amphibian tractor troops left behind to assist with the redeployment of remaining X Corps elements to south Korea. The 1st Marine Division and 1st Marine Aircraft Wing were separated for the first time since the Inchon landing. VMF-311, the new Panther jet squadron, was flying from K-9, an Air Force field near Pusan. Operating together as an all-Marine carrier group taking part in the Hungnam redeployment were the three Corsair squadrons: VMF-212 on the CVL (light carrier) _Bataan_; VMF-214 on the CVE _Sicily_; and VMF-323 on the CVE _Badoeng Strait_. The two Japan-based night fighter squadrons, VMF(N)-542 and VMF(N)-513, flying from Itazuke, patrolled the skies between Japan and Korea.