Pierced Steel Planking

Marston Mat (also known as pierced (or perforated) steel planking (PSP)), is standardized, perforated steel matting material originally developed by the United States at the Waterways Experiment Station shortly before World War II, primarily for the rapid construction of temporary runways and landing strips. (The name is also misspelled as Marsden matting.) The nickname came from Marston, North Carolina adjacent to Camp Mackall airfield where the material was first used.

PSP consisted of steel strips with punched lightening holes in it. These holes were in rows, and a formation of U-shaped channels between the holes. Hooks were formed along one long edge and slots along the other long edge so that adjacent mats could be connected. The short edges were cut straight with no holes or hooks. To achieve lengthwise interlocking, the mats were laid in a staggered pattern.

The hooks were usually held in the slots by a steel clip that filled the part of the slot that is empty when the adjacent sheets are properly engaged. The holes were bent up at their edges so that the beveled edge stiffened the area around the hole. In some mats a T-shaped stake could be driven at intervals through the holes to keep the assembly in place on the ground. Sometimes the sheets were welded together.

A typical Marston mat was the M8 landing mat. A single piece weighed about 66 pounds and was 10 ft (3.0 m) long by 15 in (0.38 m) wide. The hole pattern for the sheet was three holes wide by 29 holes long resulting in 87 holes per mat.

A variation made from aluminum was produced to allow easier transportation by aircraft, since it weighed about 2/3 as much. It was referred to as PAP for perforated aluminum planking, but was not as common as aluminum was a controlled strategic material during World War II.

After the war PSP was used by many southeastern U.S. auto racing teams since it was manufactured in the area, and used in many abandoned military airfields. It was also used during a similar period when NASCAR teams used car trailers.

Marston Mat was extensively used during World War II by Seabees (construction battalions) and other front line construction personnel to build runways and other readily usable surfaces over all kinds of terrain. The first (experimental) use of PSP was in 1942/1942 for constructing a 5,000 foot runway on Greenland's 'Bluie West One' (BW-1), an Allied Ferry Command and U.S.A.A.F airfield located on the extreme southwest corner of Greenland's landmass, at the termination of Eriksfjord, and near the coastal community of Narsarsuaq. Deemed a success, it was then used extensively in the Pacific Theater of Operations. A C-47 Skytrain supply aircraft was the first plane to land on the first steel-mat runway constructed in France after the invasion of Normandy.

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