Russian aircraft builders display great ingenuity in wringing every last ounce of performance from existing machines. The long-lived Su 17 is such an example, and it continues to be upgraded and employed long after the basic design became obsolete.
In 1956 the Sukhoi design bureau created its first tactical jet bomber, the Su 7, a modern-looking machine built in large numbers to offset its relative simplicity. It was a capable fighter-bomber and ruggedly built but also somewhat underpowered. Moreover, it suffered from long runway rolls and rather short range. In 1967 the Sukhoi bureau decided to upgrade this family of bombers by adding variable-geometry wings to enhance takeoff, landing, and load-carrying abilities. Early on it was judged impossible to fit wing-retracting equipment into the narrow fuselage, so engineers compromised by making the wings pivot midway along their length. The added lift increased the Su 7’s takeoff performance, and operational radius and ordnance payload were improved as well. Commencing in 1971 the new Su 17 became operational in large numbers, and they were deployed by Warsaw Pact allies and Soviet client states. It has since received the NATO designation FITTER.