Air Transport Services Group Inc. is an American aviation holding company which provides air cargo transportation and related services to domestic and foreign air carriers and other companies that outsource their air cargo lift requirements. ATSG, is the world's largest lessor of converted Boeing 767 freighter aircraft through its leasing division, Cargo Aircraft Management. Through its principal subsidiaries, including three airlines with separate and distinct U.S. FAA Part 121 Air Carrier certificates, ATSG provides aircraft leasing, air cargo lift, passenger ACMI and charter services, aircraft maintenance services and airport ground services. ATSG's subsidiaries include Cargo Aircraft Management; ABX Air; Air Transport International; Omni Air International, Airborne Global Solutions; Airborne Maintenance & Engineering Services, including its subsidiary, Pemco Conversions dba Pemco World Air Services; and LGSTX Services. ATSG owns a 25 percent equity interest in West Atlantic. Wikipedia