The Sukhoi Su-33 is an all-weather carrier-based twin-engine air superiority fighter designed by Sukhoi and manufactured by Komsomolsk-on-Amur Aircraft Production Association, derived from the Su-27 and initially known as the Su-27K. Compared with the Su-27, the Su-33 has a strengthened undercarriage and structure, folding wings and stabilators, all for carrier operations. The Su-33 has canards and its wings are larger than the Su-27 for increased lift. The Su-33 has upgraded engines and a twin nose wheel, and is air refuelable.