April to July of 1965: NMCB 10 and the Sands of Chu Lai

By Dr. Frank A. Blazich Jr., Historian, U.S. Navy Seabee Museum, Naval History and Heritage Command
Photos courtesy of the U.S. Navy Seabee Museum

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Today, the settlement of Chu Lai in Quảng Nam Province, Vietnam, is home to an open economic zone featuring an industrial park serviced by a seaport and the Chu Lai International Airport. All of these are notable attributes considering that Chu Lai, prior to 1965, did not formally exist on any map. The name and the airport entered the history of Vietnam and the United States in the first half of 1965, when Marines and the Seabees of Naval Mobile Construction Battalion (NMCB) 10 arrived and turned the coastal area into a major military installation. From May 7 to July 3, 1965, the “Men of Ten” overcame numerous obstacles at seemingly every turn to construct an 8,000-foot expeditionary airfield. Furthermore, the construction of this field at Chu Lai came during the pivotal period of America’s involvement in Vietnam, which would end in July with American forces engaged in offensive ground operations.

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Fifty-seven miles south of Da Nang, Chu Lai consisted of only a handful of small Vietnamese settlements until the Seabees of NMCB 10 arrived in May 1965. The name “Chu Lai” is often credited to U.S. Marine Corps Lt. Gen. Victor H. Krulak, who used the Mandarin Chinese characters for his name to title locations on the maps. 

To place the deployment of NMCB 10 to Chu Lai in proper perspective, a brief overview of the political and military situation is necessary. Following his overwhelming electoral victory in the 1964 presidential election, President Lyndon B. Johnson turned his attention in early 1965 to the military situation in South Vietnam. With political instability in Saigon and South Vietnamese military forces suffering defeat in the field against members of the National Liberation Front (Viet Cong), Johnson and his advisors authorized a series of gradually escalating, retaliatory air strikes in February 1965. Through a strategy of limited war with progressively applied force, Operation Rolling Thunder’s air campaign committed the military to increasing levels of pressure to force the North Vietnamese to change its policies. This strategy, however, only served to increase rather than limit the U.S. military effort. By month’s end, Johnson authorized the deployment of two Marine battalions to Da Nang to defend the American air base.

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These photos, taken by the survey team on April 3, 1965, depict conditions at the construction location. (Clockwise, starting with top left) Aerial view of north end of site; view north along plateau inland from tree line; view south along plateau inland from tree line; and view southeast along plateau parallel to axis of expeditionary runway. 

When the military and diplomatic situation failed to improve by March, Gen. William Westmoreland, commander, Military Assistance Command, Vietnam, requested more ground forces for offensive operations. Johnson, fearful of domestic blowback from deploying ground forces while committed to his limited war of gradual escalation, chose to implement a compromise. On April 20, 1965, military officials agreed to an “enclave strategy,” whereby American forces would establish bases around key coastal areas with authorization to assist the South Vietnamese military up to 50 miles from the base perimeters in combating Viet Cong forces. This compromise strategy, brainchild of Ambassador Maxwell Taylor, was not supported by the Joint Chiefs of Staff or Westmoreland, but Johnson hoped it would stabilize the military situation in South Vietnam long enough for the air campaign to produce the desired shift in Communist policy. At the April 20 meeting, participants agreed that the Marines would establish an enclave at Chu Lai with an expeditionary airfield, 57 miles southeast of Da Nang.

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Equipment operations of NMCB 10 grading and preparing a taxiway site, looking east in May 1965. Note that one tractor is pulling the scraper, while a bulldozer is pushing due to the softness of the sands. 

Unlike the Marston matting and crushed coral of World War II, the Marines would call on the Seabees to construct an evolution in tactical airfields. The Short Airfield for Tactical Support (SATS) essentially took a carrier flight deck and set it ashore. Developed by the Marine Corps, the SATS field used AM-2 aluminum slab matting to form the runway, each piece measuring 12 feet by 2 feet, weighing 144 pounds. This smooth surface would be mated together with a catapult system, arresting gear, carrier lighting system, expeditionary control tower, and a fuel dispensing system to allow Douglas A-4 Skyhawks to land and perform catapult or jet-assisted takeoffs. While initially designed as a 3,000-foot-long, 72-foot-wide runway, the Marines at Chu Lai increased the field to a final size of 8,000 feet by 102 feet, with accompanying matted taxiways. The Seabees factiously dubbed this the LATS, “Long Airfield for Tactical Support.” On March 30, Secretary of Defense Robert S. McNamara tentatively approved the field, which would relieve the overcrowded conditions at Da Nang.  Final approval did not arrive until the conference on April 20. Prior to any final decision, however, a thorough reconnaissance of the site would be necessary to ascertain the feasibility of building at Chu Lai.

Thus began the start of NMCB 10’s involvement with Chu Lai. While the battalion prepared to deploy from Port Hueneme, Calif., to Okinawa as the Pacific Alert Battalion, the battalion Operations Officer Lt. Frank M. Newcomb joined a party of three officers of the First Marine Air Wing (1st MAW) to inspect the proposed location at Chu Lai. Arriving by helicopter on the morning of April 3, 1965, Newcomb and the team found the proposed construction site to be a plateau of firm, fine sand, sparsely covered with grass adjacent to a wide lowland area. Soil samples were not taken and looking away from the potential construction site the team spied a low hill of laterite material (soil high in iron and aluminum) which they believed could be used to stabilize the sands. With reports of active Viet Cong forces in the area, the ground reconnaissance lasted less than two hours, restricted to what essentially became the southern half of the runway. In his report on the reconnaissance, Newcomb requested soil samples of the sand and laterite, but the Marine officers developing the airfield plans assumed the survey area represented the whole of the construction site. In the haste to meet deadlines, the samples were forgotten.

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To stabilize the subgrade prior to placing the runway and taxiway matting, CEC officers opted to use locally available laterite, a soil rich in iron and aluminum. The volume of laterite continued to increase until a method was devised to stabilize Chu Lai’s sands. 

Newcomb returned to Okinawa to share his findings with recently arrived NMCB 10, while the Marine officers put the finishing touches on the blueprints for the expeditionary airfield. Based on the assumptions and site survey, the planners estimated that the SATS field could be operational in 21 days and would require 1.4 million square feet of matting. This figure represented literally the entire Marine Corps inventory of matting in the Far East. With an amphibious landing of the entire construction battalion scheduled in May, NMCB 10 requested more detailed plans of the airfield. Despite expressing concerns about the construction schedule, they only received rough details of the overall plan, forcing the Seabees to make educated assumptions on the allocation requirements in equipment for construction. Nevertheless, Johnson approved construction of the field on April 25, and NMCB 10 left Okinawa on April 29 destined for Chu Lai, confident in its ability to meet the timetable and overcome the unknowns of the construction site.

In the morning hours of May 7, 1965, the 3d Marine Expeditionary Brigade (MEB) came ashore at Chu Lai. On pontoon causeways manned by a detachment of Amphibious Construction Battalion 1, the 600 “Men of Ten” led by Cmdr. John M. Bannister, CEC, followed the Marines ashore. When the Seabees attempted to unload the LSTs, LCMs and LCUs, the beach sands soon proved a nightmare. Without adequate shore party support, the Seabees offloaded the majority of their equipment themselves. Thankfully, the tractors were first off the causeways and made it ashore without issue, but the trucks’ tires sank heavily into the fine, soft sand. Working in temperatures over 100 degrees F with 100 percent humidity, muscle power lightened the trucks, reduced the tire pressures and laid matting to form roads to the Seabee camp. Throughout the night, teams labored to locate and deliver all of the battalion’s equipment to the camp.

With Camp Bannister’s development underway, work immediately turned to preparing the airfield site. After numerous delays, NMCB 10 received the final coordinates of the centerline of the airfield at sea on May 5. When the survey party located the coordinates on May 8, they discovered the location aligned with an April 3 range marker, but that the overall location proved unsuitable for construction of the taxiways, parking apron and maintenance area. These areas now would be located on lowland areas prone to flooding in the monsoon season. With limited time and options, the Seabees, engineers of the 1st MAW, and commander of the 3d MEB, Brig. Gen. Marion E. Carl, agreed to shift the centerline coordinate 500 yards to minimize the amount of grading and earthmoving, which still increased several times past initial estimates.

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The hillside 1.5 miles from the construction site shrank substantially with the removal of 64,500 cubic yards of laterite. 

Excavation and grading of the airfield site began on May 9. To fulfill the requirements of the airfield, approximately 183,000 cubic yards of sand were moved to construct the runway and taxiways, 46,000 cubic yards moved for squadron and base operations areas, and 180,000 cubic yards of sand moved to provide adequate drainage and remove obstructions for aircraft navigation. In the extreme temperatures, high humidity and constant sands, NMCB 10’s equipment operators sitting in open cabs found conditions hellish. The wheeled tractors intended to pull the scrapers bogged down in the sand and had to be pushed through all phases of operation. Sand worked its way into the bearings, brake linings and clutches of the tractors and trucks, reducing the battalion’s equipment to a daily average of four TD-18 dozers, one 10-yard scraper and two D8H dozers. Eventually the 3d MEB at Da Nang sent NMCB 10 all of its heavy equipment aside from a lone dozer. The extreme climate in conjunction with the heat of the engine exhaust forced the Seabees to alternate crews every 30 minutes. Undaunted, the work continued 24 hours a day and the outline of an airfield soon became obvious to aerial observers.

The sands of Chu Lai, however, would not be easily surmounted. During planning stages, engineers assumed that a six- to eight-inch layer of compacted laterite spread over the graded surface would contain the sand and serve as a sub-base for the AM-2 matting. Prior to embarking from Okinawa, NMCB 10 learned that the laterite observed during the April 3 survey was clayey and unsuitable for stabilization purposes. An alternative of using a sand-asphalt mix was suggested. When Civil Engineer Corps (CEC) officers tested this method at Chu Lai, the sand and asphalt would not mix properly. Attempts at applying the asphalt directly to the wetted sands barely penetrated beneath the surface. With a timetable to meet, the Seabees returned to using the laterite, which had proven itself in stabilizing the roads around Camp Bannister and the construction site. Commencing on May 15, excavators began chewing up a hill 1.5 miles from the airfield, eventually moving 64,500 cubic yards to stabilize the runway and taxiway areas.

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NMCB 10 mat-laying crews placed AM-2 mats down on the runway for the Short Airfield for Tactical Support (SATS). At 144 pounds per panel, high temperatures and high humidity made the work a test in endurance. 

Mat laying commenced on May 16. Due to a limited amount of AM-2 matting, the Seabees resorted to using older, heavier (165 pounds per panel) M8A1 and M8A2 matting for the taxiway, parking aprons and maintenance areas. The different panels did not seamlessly integrate, but with careful planning and rotation of crews mat laying proceeded at a daily rate of 500 feet; by May 22 approximately 2,300 feet of AM-2 runway matting was emplaced. At month’s end, the runway neared 4,000 feet in length with 1,000 feet of taxiway matted. On June 1 in the clear Chu Lai morning, Col. John D. Noble, commander, Marine Air Group 12, led a four-man formation of A-4s which touched down at the field. Another flight of four A-4s from VMA-225 and VMA-311 touched down shortly thereafter. Just after 1 pm, four VMA-225 aircraft took off to conduct air strikes six miles north of the field. Despite the odds, “Can Do” had prevailed again, proving the SATS concept worked in the most difficult of circumstances.

A few days before Noble brought the first A-4s to Chu Lai, the monsoon rains began to fall. It rained continuously from May 29 – 31. After two days of flight operations, on June 3 the center of the runway had settled two inches. Assessing the situation, the Seabees dug two ditches three to four feet deep paralleling the runway and taxiway and filled them with laterite. Removing the AM-2 mat at set intervals, the graded sand between the trenches was soaked with salt water pumped up from the beach and puddled by vibratory compaction. Next, spreaders layered 10 inches of laterite over the sand, followed by two sealing coats of asphalt finished off with a blotter of sand. Once complete, mat-laying proceeded unabated. By mid-June, over 4,600 feet of matting was laid and over 5,600 feet of runway stabilized with the new sealing method. The last piece of AM-2 matting was locked into place on July 3, 1965, completing the 8,000-foot runway and accompanying taxiways. Brig. Gen. Keith B. McCutcheon, commander of the 1st MAW, expressed his appreciation for NMCB 10’s work with a hearty “well done,” adding that, “Never wavering, never hesitating, NMCB 10 rose to meet each new problem . . . and licked them all to their everlasting credit.”

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Teams of Seabees operated in shifts to place the AM-2 matting. Here a team can be seen placing matting on the runway, two holding each panel and two assisting with alignment and hinging of the mat plates. 

After two months of construction at Chu Lai, however, the situation in South Vietnam had significantly changed. In May and June, battles at Ba Gia and Dong Xoai, where CM3 Marvin G. Shields would fall, demonstrated the weakness of the defensive-minded enclave strategy. In both battles, American forces were available but not deployed to reinforce the South Vietnamese forces. Following Dong Xoai, Westmoreland requested and received authority from Johnson for the deployment of additional ground forces to conduct offensive operations in South Vietnam, thereby signaling the end of the enclave strategy in favor of “search and destroy.” As NMCB 10 continued to build Marine Corps facilities at Chu Lai, the die for a long-term American involvement in Vietnam had been cast. With the expeditionary airfield fully operational, construction of a permanent 10,000-foot concrete runway commenced, completed in October 1966. The SATS field remained operational at Chu Lai throughout the war, although as a secondary field to the concrete runway. On September 10, 1965, NMCB 10 renamed the Seabee camp at Chu Lai Camp Shields, in honor of the fallen hero of Dong Xoai.

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While the runway matting had priority, work progressed on the taxiways as well. Here a team installs matting on the taxiway, facing north. 

The Seabee accomplishment at Chu Lai would be the first of many notable construction projects in South Vietnam. Perhaps the most powerful lesson to emerge from Chu Lai was a need to carefully evaluate and survey the geological and climatological conditions for any future construction sites. Chu Lai’s sands and high temperatures delayed construction, but as with so many issues, careful planning and Seabee resourcefulness made the impossible possible. In the years to come, the Chu Lai experience constructing the first deployed SATS airfield would be disseminated and incorporated into the projects of the 26,000 Seabees who followed the “Men of Ten” across the span of South Vietnam.

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Work continued in shifts, 24 hours each day. In the cooler evening temperatures, crews painted the runway center line strips. 

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In July, NMCB 10’s Airfield Lighting Crew from Bravo Company began to install and maintain the lighting systems for the SATS airfield. With an A-4 on final approach behind him, CEP3 Ray Trevino (foreground), Phoenix, Ariz., wires in approach lights. 

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After heavy rains affected the laterite and softened the sands beneath the runway, NMCB 10 had to remove sections of the runway to stabilize the subgrade. Here, additional laterite is being applied at the southern end of the runway. 

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Aerial view of the finished 8,000-foot SATS expeditionary airfield in July, with view north to south (left to right). The USMC A-4 attack jets are seen here with revetments in place, and one on takeoff at the north end of the runway. Camp Bannister (later Camp Shields) is visible in the tree line separating the South China Sea from the airfield. 


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