Returning to the Yudam-ni area, it may be recalled that Lieutenant Colonel Taplett’s 3/5 had passed through 3/7 at 1500 on 1 December with a mission of attacking astride the MSR to lead the way for the main column. Tank D-23, a How Company platoon and a platoon of Able Company engineers set the pace, followed by the rest of How Company and the other two rifle companies. After an advance of 1400 yards the battalion column was stopped by heavy CCF fire from both sides. How and Item Companies fanned out west and east of the road and a longdrawn firefight ensued before the Marines cleared the enemy from their flanks at 1930.[520] [520] Descriptions of 3/5 operations in this section are based on the 3/5 _SAR_, 15; Taplett and Whipple, “Darkhorse Sets the Pace,” II, 46-50; Taplett Comments, 9 Aug 56. Artillery support for the breakout was provided by 1/11 and 3/11 (minus Battery H). The plan called for 1/11 to take the main responsibility for furnishing supporting fires at the outset while 3/11 displaced as soon as possible to the vicinity of Sinhung-ni, whence the last lap of the march to Hagaru could be effectively covered. The 1st Battalion would then join the vehicle column and move with it to Hagaru.[521] [521] 11thMar _SAR_, 7; _MCB Study_, II-C-72. Taplett gave 3/5 a brief rest after securing his first objectives--the high ground on both sides of the road just opposite the northern spurs of Hill 1520. Then he ordered a renewal of the attack shortly before midnight. How Company on the right met only moderate opposition, but was held up by the inability of Item Company to make headway against Chinese dug in along the western slope of Hill 1520. Neither 1/7 nor 3/5 had any idea at the moment that they were simultaneously engaged on opposite sides of the same great land mass, though separated by enemy groups as well as terrain of fantastic difficulties. So rugged was this mile-high mountain that the two Marine outfits might as well have been in different worlds as far as mutual support was concerned. Item Company stirred up such a hornet’s nest on the western slope that Captain Harold O. Schrier was granted permission by the battalion commander to return to his jump-off position, so that he could better defend the MSR. There he was attacked by Chinese who alternated infantry attacks with mortar bombardments. Radio communication failed and runners sent from the battalion CP to Item Company lost their way. Thus the company was isolated during an all-night defensive fight. Second Lieutenant Willard S. Peterson took over the command after Schrier received a second wound. Taplett had ordered his reserve company, George, and his attached engineers into defensive positions to the rear of Item Company. The engineers on the right flank were also hit by the Chinese and had several wounded, including the platoon commander, First Lieutenant Wayne E. Richards, before repulsing the attack.