On 21st December 1988 there was made a test flight of a transport aircraft An-225 Mrija. It is currently the biggest and heaviest aircraft. It was originally designed to transport space shuttle called Buran, but now it is used for commercial flights. Construction of An-225 is a little smaller that An-124. Mrija has 6 jet engines instead of four, it is also longer and has a longer wingspan. A hold enables to carry 250 t of cargo.