Control over the landings and takeoffs on the two Hill 884 sites was exercised by a hovering helicopter. Aircraft landed at 30-second intervals, each carrying five fully equipped men who disembarked in average time of 20 seconds. Two radio nets maintained communications between the landing sites and orbiting aircraft. Voice contact could not be established between the landing point team and X-83, however, and it became necessary for a helicopter to return within sight of the field to restore communications for incoming aircraft. A total of 224 men, including a heavy machine gun platoon from 2/7, was lifted in flight time of 31.2 hours and over-all time of four hours. In addition, 17,772 pounds of cargo were landed. Operation SUMMIT ended with the laying of two telephone lines between Recon Company on Hill 884 and the CP of the 1st Marines, about eight miles to the rear. Fifteen minutes were required for dropping each line. The ROKs, following their relief, proceeded on foot to their own Corps area. From a tactical viewpoint, the importance of Hill 884 lay in its domination of enemy-held terrain. The difficulty of reaching the remote position had been overcome by the helicopter, and Operation SUMMIT was recorded in front page headlines by Stateside newspapers. Congratulations poured in from all sides. Lieutenant General Lemuel C. Shepherd, Jr., commanding general of FMFPac, complimented HMR-161 on “a bright new chapter in the employment of helicopters by Marines.” Major General Clovis E. Byers, commanding X Corps, praised the “organic and attached units of the 1st Marine Division that participated in the first relief of units on the battle position. Your imaginative experiment with this kind of transport is certain to be of lasting value to all the services.”[307] [307] Messages of congratulation are quoted from HMR-161 _HD_, Sep 51. Nobody was more enthusiastic than General Thomas. “Operation SUMMIT, the first helicopter-borne landing of a combat unit in history, was an outstanding success,” said his message. “To all who took part, well done!” [Illustration: HMR-161 OPERATIONS 1951 MAP 21] _Helicopter Operation_ BLACKBIRD It is not surprising, considering their training, that the Marines found it a difficult transition from offensive to defensive operations after 20 September. As evidence that patrols were conducted with customary aggressiveness, Marine casualties (including the 1st KMC Regiment) for the last 10 days of the month were 59 KIA, 1 MIA, and 331 WIA. Enemy losses for the same period were 505 counted KIA, and 237 prisoners. 1st Marine Division casualties of 2,416 (including 594 reported by the KMCs) for September as a whole were the most severe suffered during any month of the war so far with the exception of December 1950 and June 1951. NKPA losses of the month were 2,799 counted KIA and 557 prisoners.[308] [308] 1stMarDiv _HD_, Sep 51, 4, 31–32.