The Su-11 was an upgraded version of the Sukhoi Su-9 ('Fishpot') interceptor, which had been developed in parallel with the OKB's swept wing Su-7 fighter bomber.

A more powerful Lyulka AL-7F-1 turbojet was installed, providing 9.8 kN (2,210 lbf) more afterburning thrust for improved climb rate and high-altitude performance (and to compensate for increased weight).

A conversion trainer version, the Su-11U 'Maiden,' was also developed; Similar to the Su-9U, it had full armament and radar systems for training purposes, but the second seat reduced its already marginal fuel capacity and was not intended for combat use.

Even with the superior radar, the Su-11 remained heavily dependent on ground control interception (GCI) to vector its pilot onto targets.

Data from OKB Sukhoi : a history of the design bureau and its aircraft[1]General characteristics Performance Armament