AAR Corporation was founded in 1951, organized in 1955 and reincorporated in Delaware in 1966. It is a diversified provider of products and services to the worldwide aviation and government and defense markets. It conducts its business activities primarily through seven principal operating subsidiaries: AAR Parts Trading, Inc.; AAR Aircraft & Engine Sales & Leasing, Inc.; AAR Services, Inc.; AAR Aircraft Services, Inc.; AAR Manufacturing, Inc.; AAR Airlift Group, Inc.; and AAR International, Inc. The Company's international business activities are conducted primarily through AAR International, Inc. It reports its activities in four business segments: Aviation Supply Chain, comprised of business activities conducted through AAR Parts Trading, Inc.; AAR Allen Services, Inc. (a wholly-owned subsidiary of AAR Services, Inc.); AAR Aircraft & Engine Sales & Leasing, Inc. and AAR International, Inc.; Government and Defense Services, comprised primarily of business activities conducted through AAR Parts Trading, Inc. and AAR Airlift Group, Inc.; Maintenance, Repair and Overhaul, comprised primarily of business activities conducted through AAR Services, Inc; AAR Allen Services, Inc. and AAR Aircraft Services, Inc.; and Structures and Systems, comprised primarily of business activities conducted through AAR Manufacturing, Inc. Activities in its Aviation Supply Chain segment include the purchase and sale of a wide variety of new, overhauled and repaired engine and airframe parts and components for its airline customers. It also repairs, overhauls and sells a wide variety of avionics, electrical, electronic, fuel, hydraulic and pneumatic components and instruments and a broad range of internal airframe components for its customers. Activities in its Government and Defense Services segment include the business of AAR Airlift Group, Inc. (Airlift) and its Defense Systems and Logistics and Integrated Technologies services businesses. Airlift is a provider of expeditionary airlift services to the United States and other government customers. Airlift provides fixed- and rotary-wing flight operations, transporting personnel and cargo principally in support of the U.S. Department of Defense, and performs engineering and design modifications on rotary-wing aircraft for government customers. Activities in its Maintenance, Repair and Overhaul (MRO) segment include major airframe maintenance inspection and overhaul, painting services, line maintenance, airframe modifications, structural repairs, avionic service and installation, exterior and interior refurbishment and engineering services and support for many types of commercial and military aircraft. It currently operates four airframe maintenance facilities and one landing gear overhaul facility. It has a long-term lease to occupy a portion of an aircraft maintenance facility in Indianapolis, Indiana (the Indianapolis Maintenance Center or IMC), which is owned by the Indianapolis Airport Authority (IAA). Activities in its Structures and Systems segment include the design, manufacture and repair of airdrop and other transportation pallets, and a wide variety of containers and shelters used in support of military and humanitarian tactical deployment activities. In this segment, it also designs, manufactures and installs in-plane cargo loading and handling systems for commercial and military aircraft and helicopters. It is a provider of complex machined and fabricated parts, components and sub-systems for various aerospace and defense programs and other applications, and it designs and manufactures advanced composite materials for commercial, business and military aircraft. In this segment, sales are made to customers pursuant to standard commercial purchase orders and contracts.