Antonov An-225 Mriya & Buran Scale Model
Not exactly a full-size plane, but still I feel like they belong here.
Antonov An-225 Mriya is the one of world's largest and highest-lift-capacity cargo planes, initially designed to carry the Soviet Buran spaceplane. Currently it serves as a super-heavy cargo lifter and holds numerous world records for cargo airlift.
Buran (Russian for "Snowstorm" or "Blizzard") was a Soviet-made equivalent spaceplane to USA's Space Shuttle program. Only a single, fully-automated and uncrewed orbital flight has ever been made, with the entire programme being mothballed and eventually abandoned due to the collapse of USSR.