Evaluation of XM20 aluminum landing mat
Burns, Cecil D.; Grau, Robert W. (Robert Walter)
Miscellaneous PaperAbstract: This investigation was conducted to evaluate XM20 aluminum landing mat fabricated by Dow Chemical Company, Madison, Illinois. The mat, fabricated from 2- by 12-ft extrusions, was similar to AM2 mat except for minor differences in the cross section of the mat and the method used to attach the end connectors to the mat extrusion. A test section consisting of one clay subgrade item at a strength of 4 CBR was constructed and surfaced with the XM20 mat. The test section was subjected to uniform-coverage traffic representing operations of an aircraft having a 60,000-lb gross weight with a single-wheel main gear assembly load of 27,000 lb with a 30x7.7 tire inflated to 400 psi. Based on the results obtained in this study, it is concluded that: (A.) The XM20 mat will sustain 1600 cycles (188 coverages) of aircraft operations with a 27,000-lb single-wheel load and 400-psi tire inflation pressure when placed on a subgrade having a CBR of 2.5 or greater throughout the period of traffic, or about 1230 coverages of the same loading when placed on a subgrade having a CBR of 4 or greater throughout the period of traffic. (B.) The service life of the XM20 mat on a 4-CBR subgrade is about six times greater than that of standard AM2 mats tested previously at WES on subgrades with a CBR of 4. (C.) General behavior of the mat in this test was greatly improved by the double thickness of the ribs at the end joints of the planks.
U.S. Army Engineer Waterways Experiment Station.Engineer Research and Development Center (U.S.)
Aluminum landing mats; Landing mats; XM20 landing mat; Airfields; Trafficability
Approved for public release; distribution is unlimited.