Antonov designed the An-22 Antheus (named for the giant son of Greek god Poseidon) to carry the Soviet Army's mightiest fighting vehicles, including main battle tanks and missile launchers. Its NK-12 turboprops, which also power the Tu-95/Tu-142 "Bear" family of Russian bombers and maritime patrol aircraft, are the most powerful turboprop engines in service. The first An-22 flew on 27 February 1965, and was publicly displayed at the Paris International Air Show later that year. The largest transport aircraft of the time, the An-22 set a number of world records. Production was ended in 1974 after approximately 75 aircraft had been delivered to the Soviet Air Force and Aeroflot. (Although primarily built for the Soviet Air Force, almost all An-22s wear the traditional Aeroflot colors. This allowed them much freer access to overflight and landing rights than had they been operated in military markings.)
Some notable features of the An-22 include the comprehensive navigation and precision drop avionics complete with three separate radars, a 14-wheel undercarriage (tire pressures can be adjusted from the flightdeck to optimize the aircraft for different airfield surfaces), a reinforced titanium floor with integral rear loading ramp, four overhead gantries and two floor winches for freight handling, twin tails, and double slotted wing flaps. Also, like the An-12, the main cargo hold is not pressurized, troops/passengers are carried in a forward cabin which accommodates 29.
After entering service, the An-22 set 14 payload to height records in 1967, the pinnacle of which was the airlift of 220,500 pounds (100 metric tonnes) of metal blocks to an altitude of 25,748 feet (7,848m). It also established the record for a maximum payload, 221,443 pounds (104,445kg), lifted to a height of 6,562 feet (2,000m). A number of speed records were also set in 1972, including a speed of 328 knots (608.5km/h) around a 540 nautical mile (1,000km) closed circuit with a 110,250 pound (50,000kg) payload. Several other speed-with-payload records were established in 1974 and 1975.
While the Antheus has been superseded by the larger, jet-powered An-124 "Condor", the surviving aircraft are still heavily utilized as they offer rare payload carrying characteristics.