AbstractThis thesis discuss how United Parcel Service (UPS) develop its aircraft maintenanceprogram after import of McDonnell Douglas MD-11aircraft and the process of exporting newMD-11 aircraft from manufacturer in USA to European operator as passenger aircraft. It alsodiscusses the process of importing the same types of aircraft as freight carrier. The aircraftundergo, through different modifications at Singapore Technologies Aerospace (STA)conversion from passenger to freight carrier, a program specially designed for UPS airlinesbefore import to USA.The thesis work was carried out in close communication with the maintenance department atUPS in California and Kentucky, McDonnell Douglas manufacturing plant in Missouri and atBoeing in Washington.The aim of this thesis was to examine and discuss the rules and regulation of import andexports of aircraft in U.S. based on UPS import of MD-11 aircraft. Furthermore, to discussthe transformation of maintenance program from one airline to another, with emphasis onhow U.S. operator develop their maintenance program.McDonnell Douglas manufactures MD-11 aircraft, and as aircraft manufacturing companythey must comply with the United States of America Federal aviation regulation part 21requirements. Besides that, the company has bilateral agreement with the buying countrySwitzerland, facilitating the reciprocal airworthiness certification of civil aeronauticalproducts exported between the two parties. Bilateral airworthiness agreement or aviationsafety agreement with implementation procedure for airworthiness facilitate the airworthinesstechnical cooperation between the Federal Aviation Administration (FAA) and its counterpartSwitzerland Civil Aviation Authorities (SCAA).UPS buy MD-11 aircraft after being modified as freight carriers. In order to obtainairworthiness certification from FAA UPS and Boeing secures that the aircraft is airworthyand have got appropriate overall maintenance service through a careful investigation processof the technical history and background of the aircraft. After receiving the FAA certificateUPS in cooperation with Boeing develop the maintenance program, before the aircraft isassigned for service in the UPS fleet.During my work it has been difficult to find information about the technical history of theaircraft, mainly because the first operator Swissair became bankrupt and all documentationwas transferred to Boeing and then to UPS. There were also many companies involved in theprocess of converting passenger aircraft to freight carrier, like ST Aero Subsidiary, Sasco inSingapore and Boeing.The work can be used as a reference to check what part of FAA deals and documents areneeded for import and export of aircraft, and what should be done to start the import andexport process. It guides the reader to an immediate understanding of regulatory organizationand their particular departments or part numbers.