The Sukhoi Su-33 Sea Flanker is the naval version of the Sukhoi Su-27 Flanker made expecifically to the Russian Navy to operate in the Admiral Kuznetsov Aircraft Carrier. The main differences of the Su-33 and the Su-27 is that the Su-33 is made for operation in aircraft carriers and the Su-33 have the capacity of aerial refueling, capacity that the Su-27 don't have.