Generally acknowledged as the largest airplane in the world, the single Antonov An-225 is the world's heaviest aircraft ever (maximum takeoff weight greater than 640 tons) and the largest Heavier-than-air aircraft (in length and wingspan) ever entering operational service.
Very large flying boat. The largest aircraft in the world 1944 to 1945 when the single one was destroyed. The even heavier Convair B-36 first flew in 1947. Heaviest aircraft built during World War II, and largest aircraft produced by any of the Axis powers in World War II
The ekranoplan had wingspan of 37.6 m, length - 92 m, maximum take-off weight - 544 tons. Until An-225 it was the largest aircraft in the world. Unit KM was tested at the Caspian Sea for 15 years until 1980. In 1980, pilot error caused a crash without human casualties. The vehicle was too heavy to be recovered from its watery wrecksite.
Largest aircraft in the world 1947 to 1952 when the even heavier Boeing B-52 Stratofortress first flew. World's largest flying boat, and largest wingspan of any aircraft. Only one was ever built and it performed only one short test flight.
Announced in 2006 as a derivative of the Airbus A380-800. World's highest-capacity passenger aircraft in history. In May 2010, Airbus announced that A380-900 development was postponed, until production of the A380-800 has stabilised.
1960s design. A mockup was built but no prototype.
Planned as an answer to the Anglo-French Concorde supersonic transport (SST). At 306 feet (93 m) long it would have been one of the longest airframes ever flown. Problems with the weight of the swing-wing mechanism and air friction heating in Mach 3 flight provoked a drastic redesign, by which time airline interest in SSTs was dropping because of environmental concerns. There was also political opposition to funding private industry. The U.S. Congress cut government funding in 1971 and airlines began canceling orders.
KR-860 (Kryl'ya Rossii or "Wings of Russia") early named as SKD-717 is super large transport aircraft with weights about 650 tonnes (Antonov An-225 weight is 600 tonnes), payload about 300 tonnes (An-225 payload is 250 tonnes) and 860 to 1000 passengers, a proposed Double decker wide-body superjumbo jet by Russian aerospace company Sukhoi.
Proposed 50-ton 52-metre wingspan design by Barnes Wallis able to carry a ten-ton earthquake bomb (of his own design) and drop it from 14,000 m on strategic targets in Germany. Rejected by RAF due to lack of usefulness for other types of missions and unlikely to be completed before end of war.