AAR provides a wide variety of aviation services and technology products primarily for the aerospace and defense industries. The company supplies commercial customers and government agencies and its contractors with aircraft components such as transportation pallets, containers, shelters, mobility systems, and control systems used in support of the deployment of military and humanitarian activities. AAR also provides inventory management and parts distribution; aircraft maintenance, repair and overhaul; and expeditionary airlift services. The company traces its historical roots to 1951, when Allen Eichner began selling aircraft radios and instruments.