The Antonov An-225 Mriya (Ukrainian: Антонов Ан-225 Мрія, l 'dream' or 'inspiration'; NATO reporting name: Cossack) was a strategic airlift cargo aircraft designed and produced by the Antonov Design Bureau in the Soviet Union.



It was originally developed during the 1980s as an enlarged derivative of the Antonov An-124 airlifter for the express purpose of transporting Buran-class orbiters. On 21 December 1988, the An-225 performed its maiden flight; only one aircraft was ever completed, although a second airframe with a slightly different configuration was partially built. After a brief period of use supporting the Soviet space program, the aircraft was mothballed during the early 1990s. Towards the turn of the century, it was decided to refurbish the An-225 and reintroduce it for commercial operations, carrying oversized payloads for the operator Antonov Airlines. Multiple announcements were made regarding the potential completion of the second airframe, however its construction has largely remained on hold due to a lack of funding. By 2009, it had reportedly been brought up to 60–70% completion.

With a maximum takeoff weight of 640 tonnes (705 short tons), the An-225 held several records, including heaviest aircraft ever built and largest wingspan of any aircraft in operational service. It was commonly used to transport objects once thought impossible to move by air, such as 130-ton generators, wind turbine blades, and diesel locomotives. Additionally, both Chinese and Russian officials had announced separate plans to adapt the An-225 for use in their respective space programmes. The Mriya routinely attracted a high degree of public interest, attaining a global following due to its size and its uniqueness.