TME Looks Back: Vietnam – “Foxholes for Aircraft”
Posted on March 7, 2016 | By Stephen Karl
This week in TME Looks Back: Vietnam, we feature the first Air Force Prime BEEF civil engineers to appear on the cover of The Military Engineer (November-December 1966) along with an accompanying Military Engineer Field Notes short article on “Foxholes for Aircraft” by Senior Master Sgt. Robert C. Bueker, USAF.
The article appears below in mobile-friendly format.
In the summer of 2016, SAME will publish a special issue of The Military Engineer commemorating the service and contributions of military engineers in the Vietnam War. As part of the run-up to the publication, we will be featuring on Bricks & Clicks a special series entitled TME Looks Back: Vietnam featuring past articles, photos, advertisements, covers, and other material that first appeared in the magazine during the 1960s and early 1970s. [The TME editorial staff welcomes input as we develop the Vietnam Commemorative Issue. Contact Stephen Karl at firstname.lastname@example.org for more information or click here to contribute editorial content. Contact Stephanie Satterfield at email@example.com for sponsorship/advertising inquiries.]
Foxholes for Aircraft
By Senior Master Sgt. Robert C. Bueker, USAF
During 1965 the Air Force shipped steel revetments to Vietnam to protect parked aircraft from damage by enemy fire and a Prime BEEF team was sent to Bien Hoa, arriving on August 8, to speed the erection of the revetments. These aircraft “foxholes” are structures of steel-copper-alloy (16-gauge) sidewalls and 8-gauge column sections, filled with sand.
Construction of the revetments could not interfere with the operations at the airfield, and had to be completed in 68 days. A strip 20 feet wide on both sides of the apron had to be constructed as a base for the revetments. This was an unforeseen job, and there was no paver, no forming materials, no concrete aggregate, and not enough labor.
Equipment for the work consisted of a “bomb damage repair kit” made up of two 2 ½-yard payloaders, fifteen 5-ton dump trucks, one road maintainer, and two TD-20 bulldozers. There was no crane hoist or drag line. To form an expedient hoist, a front-loader was rigged with steel cable slings to fit through the column sections and onto the teeth of the bucket (see TME Nov-Dec 1966 cover). In this manner, the prefab sections were carried from the assembly area to the revetment ramp.
Bins were laid out for storage of all parts in a pattern that would require the least movement for prefabrication. Pierced steel planking (PSP) was laid down for a working surface. Sand was supplied by local contractors; aggregate was purchased from the prime contractor in Southeast Asia, RMK; transporting of equipment and supplies, excavating, and forming were by the Prime BEEF crew with help from local Vietnamese workers. Wood was not available from the heavily forested jungles because they are in Viet Cong territory, so forming material had to be imported. For placing the 6-inch concrete slab, a paver was lent and operated by RMK.
Laterite was used as backfill in the lower 6 feet of the 12-foot revetments, but presented a problem. Water suspension in the sand-clay mixture is nearly 100 percent. Eight feet of fill placed in the revetment walls would shrink to 4 feet when dried.
Before the walls could be erected it was necessary to set up an improvised anvil made of a piece of channel iron supported on steel A-frames for use in repairing and straightening the revetment steel which had been severely damaged in transport. As the daily monsoon rains fell, repair of damaged materials continued in the anvil tent. Outside, the battle of mud went on. Each afternoon, the heavy deluge would wash soil back into areas cleared for forming the perimeter slab.
Fourteen walls, 70 feet long and 5 ½ feet thick, were, at last, erected (Figure 17) and backfilled (Figure 18). Prefabricated interior column sections were hauled to the construction area on the bucket of the front-loaders and held in position until four pieces of side framing were attached. While other crew members worked on finishing the side panels, the loaders returned to the prefab yard for additional column sections. With this basic protection provided, the crew completed the concrete apron extensions before the arrival of the remaining steel. When it came, the work moved rapidly, and eighteen revetments were completed and backfilled with laterite and sand by October 15, 1965 (Figure 19).
To prevent erosion by wind and rain, the upper 4 inches of backfill sand was crowned and stabilized with cement at a ratio of 4 sacks per cubic yard. To prevent overheating of jet engines through recirculation of hot exhaust gases within the revetment walls, reinforced PSP jet blast deflectors were installed.
In all, 35 work days were used in erecting over 3,800 linear feet of revetment wall, 12 feet high and 5 ½ feet wide. Total lapsed time was the allotted 68 days.
The experiences of this team and the lessons learned have been passed on to other Prime BEEF teams being deployed to Vietnam to continue the project for the protection of combat aircraft which are a vital factor in the defense of Vietnam.
[reprinted from TME / November-December 1966]