The Chosin Reservoir campaign opened two new chapters in Marine aviation history. The first was the use of the airborne TADC to control the air support of the division column between Hagaru and Chinhung-ni. The second was the appearance of VMF-311, the first Marine jet squadron to fly in combat. Beginning on 10 December the newly arrived squadron flew interdiction missions for four days from Yonpo. Then it moved to Pusan to operate for the remainder of the month with 5th Air Force jets streaking up the long peninsula to cover the withdrawal of the Eighth Army.[650] [650] 1stMAW _SAR_, annex K, appendix F (VMF-311), 2; VMF-311 _HD, Dec 50_. Appreciation for the assistance given by Marine aviation to Marine ground forces was expressed in a letter of 20 December from General Smith to General Harris, the Commanding General of the 1st Marine Air Wing. The Division Commander said: Without your support our task would have been infinitely more difficult and more costly. During the long reaches of the night and in the snow storms many a Marine prayed for the coming of day or clearing weather when he knew he would again hear the welcome roar of your planes as they dealt out destruction to the enemy. Even the presence of a night heckler was reassuring. Never in its history has Marine Aviation given more convincing proof of its indispensable value to the ground Marines. A bond of understanding has been established that will never be broken.[651] [651] MajGen O. P. Smith ltr to MajGen F. Harris, 20 Dec 50. The story of air support in the Chosin Reservoir campaign would not be complete without a summary of the results of VMO-6. Marines took a proprietary interest in Major Gottschalk’s squadron, which had put into effect the helicopter techniques worked out at Quantico by the experimental squadron, HMX-1. Some of these techniques were having their first test in combat, for the development of rotary-wing aircraft in 1950 was at a pioneer stage comparable to that of fixed-wing aircraft in the first year of World War I. On 28 October, VMO-6 had a strength of 25 officers, 95 enlisted men, ten light fixed-wing aircraft (eight OY-2s, two L5Gs) and nine HO3S-1 helicopters. From that date until 15 December the squadron made 1544 flights for a total of 1624.8 hours. The principal missions were as follows: Reconnaissance--OYs, 393; helicopters, 64; Transportation--OYs, 130; helicopters, 421; Evacuation--OYs, 29; helicopters, 191; Liaison--OYs, 35; helicopters, 90; Artillery spot--OYs, 39; helicopters, 0; Utility--OYs, 26; helicopters, 60; Rescue--OYs, 0; helicopters, 11.[652] [652] VMO-6 _SAR_, 20; LtCol V. J. Gottschalk, _Transcript of Informal Remarks at HQMC_, 17 May 51.