152 PacFlt EvalRpt No. 4, p. 10-198.

A Marine pilot joining the wing could expect his assignment to last for 6 to 9 months. Personnel in a nonflight status had longer tours of 10 months to a year. Wing replacements were made on an individual basis, although there were plans that by mid-1953 a new policy of at least partial squadron replacement would be in effect. That 1st MAW squadrons were able to operate effectively on an individual replacement system was attributable to the peculiarity of combat conditions in Korea. Absence of real enemy aerial opposition permitted the use of basic, parade-type flight formations and non-tactical approaches and attacks. An unusually high-level of experienced pilots in each of the two wing groups helped in the establishment of training programs and operational doctrine. The FAF limitation of four aircraft per flight eliminated the problem of large-scale, precombat squadron training as well as the difficulty of controlling and coordinating a large number of planes in a strike.

Logistical Operations, Summer 1952153

153 Unless otherwise noted, the material in this section is derived from: Selden, Div Staff Rpt; PacFlt EvalRpts No. 4, Chap. 9, No. 5, Chap. 8; 1stMarDiv, 1st EngrBn ComdDs, Jun-Jul 52.

Logistical support of the division and wing remained largely unchanged through July. Several modifications did take place, however, and these were:

(1) The change of responsibility for logistical support of ground-based units in Korea from Commanding General, 2d Logistical Command to the Commanding General, Korean Communication Zone (CG, KComZ).

(2) The opening of a pipeline system for resupply of aviation fuel at K-3, beginning in May.

(3) The beginning of increased support for airbase maintenance at those airfields housing Marine squadrons.

Resupply of common items used by both Marine and Army units was still being hampered by the Marines’ limited knowledge of the Army supply system in effect and by their inability to obtain the catalogues, orders, and directives essential for requisitioning.

Two logistical operations, both of an engineering nature, took place between May and July 1952 in western Korea. One was Operation TIMBER, undertaken to provide lumber required to complete the bunker construction on the JAMESTOWN, WYOMING, and KANSAS lines. The division had estimated that three million linear feet of 4 x 8-inch timbers would be needed. Since lumber in this amount was not available through supply channels or standing timber in the division sector, Corps assigned the Marines a wooded area 50 miles to the east in the U.S. 45th Infantry Division sector. On 12 May a reinforced engineer platoon, under Second Lieutenant Roger E. Galliher, a truck platoon, and 500 Korean Service Corps (KSC) laborers,154 began the cutting, processing, and hauling of timbers which were then trucked to the railhead. Between 500 and 1,000 logs were cut daily. When the operation ended in July a total of 35,194 sections of timber had been cut. This was still not enough lumber to complete the required construction. Eighth Army then made up the difference, mostly with 12 x 12-inch timbers 30 feet long; these the Marine engineers cut to 4 x 8s for standard bunker construction.155

154 The KSC was a ROK quasi-military organization for logistical support of the UNC. Personnel were drafted from those rejected for Army service. Each KSC unit had a cadre of ROK officers and enlisted. All types of labor except personal services were performed by these Koreans. During its period in western Korea, the 1st Marine Division was supported by the 103d KSC Regiment of 5,222 men. CG, 1stMarDiv, Civ Afrs and KSC, pp. 8–9.

155 Col Harry D. Clarke ltr to Hd, HistBr, G-3 Div, HQMC, dtd 1 Sep 66.

Operation AMAZON, published by I Corps on 12 June, ordered that bridging preparations be made for the approaching summer flood season. The previous August at the Honker Bridge, the one nearest the railhead, the Imjin had crested some 27 feet above normal. One reason for the precautionary efforts taken to insure bridge security during the flood season was the potential damage the Chinese could cause. Since they controlled the upriver area of the Imjin, before it entered the division sector, they could introduce floatable debris or explosives into the swift running flood waters. Another major concern was the logistical problem that would be faced by forward MLR units in event the bridges became impassable and the enormous strain that would thus be placed on helicopter resupply operations.

The I Corps directive specified that its divisions maintain a transport capability that would enable medium tanks to pass safely over bridges spanning the major rivers in their I Corps sector. The order also called for the removal of debris that could cause damage to bridges. Removal of those bridges vulnerable to flood conditions and the erection of emergency river spans were also to take place on corps order.

To carry out the I Corps operational order, General Seiden put the division’s own AMAZON plan into effect on 1 July. On this date Companies A, B, and D of Lieutenant Colonel Harry D. Clarke’s 1st Engineer Battalion began extensive preparations for debris removal from the four bridge sites in the division sector. Even before this, Marine engineers and shore party personnel had been trained at special schools to handle U.S. Army equipment provided for the AMAZON operation.156

156 This included employment of the 60-inch searchlight for night illumination, maintenance of boats for debris removal, and operation of the M-4 ferry. Other preparations by the division, of a non-engineer nature, included positioning of 13,000 life-saving floatation devices for use by frontline troops should they become shut off from planned evacuation.

Beginning 1 June, division engineers began blasting away at objects that flood waters could loosen and carry into the bridge supports. Bridge approaches were improved and their supports strengthened. Each company had a detail living at the bridge site for which it was responsible. With the advent of heavy rains, these Marines were to operate 24-hour boat patrols to keep the river free of debris. The engineers were also to maintain a round-the-clock debris watch at the four division bridges—Freedom Gate, or the Munsan-ni Railroad Bridge in the left regimental sector; Honker and X-Ray in the center; and finally, Widgeon, very close to the Commonwealth boundary.

Heavy rains began on 27 July and continued until the 30th. On the first day the decking of Widgeon Bridge was completely submerged and Honker was removed to prevent its being carried away. Precipitation increased on 28 July and reached its peak on 29 July when 3.66 inches of rainfall were recorded. By the 30th, the rains had subsided but not before the overflowing Imjin had collapsed the X-Ray bridge. During the height of the four flood days, engineers fought the rains, flooding waters, and floating debris. The major effort took place downstream to save the Freedom Gate Bridge.

Assigned personnel removed debris from the bridge supports, guided large, dangerous pieces away with poles, while upriver the boat teams blasted still larger sections into manageable chunks that would pass between the bridge supports. These engineer efforts, in addition to regular repair and maintenance of the large road net, constituted the major ground activity in the 1st Marine Division sector in late July. August would bring more rains and emergency demands on the engineers, but the critical ground activity at that time would be directed against the Communists in the area around Bunker Hill.