Aircraft Equipment Shock And Vibration Isolation Elastomer Mount System:

Department of Defense has issued various directives permitting utilization of so-called “commercial-of fthe-shelf” (COTS) technology for Naval aircrafts. However, COTS equipment tends to have limited capabilities to withstand shock and vibration motions and tends to be unsuitable for being rigidly mounted to aircraft structures. Therefore, COTS equipment usually requires isolation shock mounts to mitigate the effects of shock and vibration presented in the naval aircraft operational environment. The major emphasis of this paper is on the development of Naval aircraft elastomer shock and vibration isolation system for sensitive electronic equipments. The primary component development goal will be in five areas: 1) Performance; 2) Durability; 3) Quality 4) certification 5) Cost. This paper covers the major steps used to develop this unique elastomer shock and vibration mount system for the sensitive aircraft electronic equipments.

American Engineering Group (AEG) has developed this unique “Dual Structure Shock Isolation Mount System” using material test, component test and finite element analysis. This new AEG equipment mount system design will allow varying static properties and provide dynamic shock and vibration mitigation over a wide load range for aircraft applications. This dual structure system provides both axial and radial damping. The equipment mount system will have two hollow spherical elements with top element functions as a “load bearing” element and the bottom spherical element as a vibration shock damping element.

This new design and elastomer formulation promises higher axial-radial stiffness, vibration damping, and extended life. Finite element results and prototype creep testing results demonstrates the optimum stiffness and creep behavior in service conditions. AEG has achieved this vibration and shock performance and durability improvement using the recent advances in material technology, processing, and design concepts. This dual element structural isolation concept is successfully used in Naval aircraft applications for vibration isolation for sensitive electronic equipments. Material choices and mount designs are established based on the requirements based on the combined axial and radial loads experienced by the current naval equipment mount systems. The dual mount design concept will be to maintain stiffness to dynamic loads, while providing enough damping to equipment vibration and shock loads. This dual mount system has offered significant improvements in reliability and durability by reducing acquisition cost, reducing inspection intervals, extending the damage tolerance threshold and improving design efficiency.