Performance of New Materials for Aircraft Arrestor Beds

The design and construction of currently employed aircraft arrestor beds requires the presence of a soft ground in which an aircraft in overrun decelerates as a result of drag forces acting on its landing gear. During this interaction, the wheels crush and/or displace the material until a complete stopping of the airplane is achieved. The arresting systems are of special importance for those airports which do not have a safety area of the length required by international regulations. In the recent past, several materials with high energy absorption capability have been proposed, but most of them have been rejected in order to reduce some secondary effects such as dust production during overrun which leads to the engine failure, short durability to environmental conditions, mobility limitations to rescue vehicles. In this paper the Authors describe the experimental investigation carried out on new materials by employing innovative testing protocols. Four low density - low compressive strength materials such as cellular mortar, cellular mortar with expanded polystyrene, expanded clay pellets with bitumen and cement binder, have been considered. Quasi-static tests have been performed to define elastic-plastic transition points, and impact tests have been considered to assess the amount of energy which can be absorbed during the collapsing phase under the gears. Performance indicators of these new materials have been highlighted in the paper and have been compared to traditional indexes normally used for the characterization of existing arrestor beds.