The Sukhoi Su-7 (NATO designation name: Fitter-A) is a swept wing, supersonic fighter aircraft developed by the Soviet Union in 1955. Originally, it was designed as a tactical, low-level dogfighter, but was not successful in this role. On the other hand, the soon-introduced Su-7B series became the main Soviet fighter-bomber and ground-attack aircraft of the 1960s. The Su-7 was rugged in its simplicity, but its Lyulka AL-7 engine had such high fuel consumption that it seriously limited the aircraft's payload, as even short-range missions required that at least two hardpoints be used to carry drop tanks rather than ordnance.
After Joseph Stalin's death, the Sukhoi OKB was reopened and by the summer, it began work on a swept-wing front-line fighter. The first prototype, designated S-1, was designed to use the new Lyulka AL-7 turbojet engine. It was the first Soviet aircraft to utilize the all-moving tailplane and a translating centerbody, a movable inlet cone in the air intake for managing airflow to the engine at supersonic speeds. The aircraft also had a wing sweep of 60ð, irreversible hydraulically boosted controls, and an ejection seat of SukhoiâÂÂs own design.
The S-1 first flew on 7 September 1955 with A. G. Kochetkov at the controls. Fitted with an afterburning version of the AL-7 engine after the first eleven flights, the prototype set a Soviet speed record of 2,170 km/h (1,170 kn, 1,350 mph, Mach 2.04) in April 1956. The prototype was intended to be armed with three 37 mm Nudelman N-37 cannons and 32 spin-stabilized 57 mm (2.25 in) unguided rockets in a ventral tray. The second prototype, S-2, introduced some aerodynamic refinements. Testing was complicated by the unreliable engine, and S-1 was lost in a crash on 23 November 1956, killing its pilot I. N. Sokolov. Only 132 have been produced between 1957 and 1960, and the aircraft entered service as Su-7 in 1959.
The first production variant: a frontline fighter that saw limited operational use in the Far East from 1958. However, in 1959, a decision was made to prioritize production of the MiG-21, thus less than 200 Su-7As were deployed. The Su-7A was retired in 1965 with operational deployment.
On July 31, 1958, Soviet tactical aviation (Frontovaya Aviatsiya, ÃÂÃÂþýÃÂþòðàðòøðÃÂøÃÂ) tasked Sukhoi with developing a ground-attack variant of the Su-7, which could replace the scrapped Ilyushin Il-40. The resulting prototype, designated the S-22, incorporated structural refinements for low-altitude operations at high-speed. The prototype first flew in March 1959; entering service in 1961 as the Su-7B.
Operationally, Su-7s were hampered by a high landing speed of 340âÂÂ360 km/h. This was dictated by the highly swept wing. Combined with poor visibility from the cockpit and the lack of an instrument landing system, operations were very difficult, especially in poor weather or airfields. In 1961âÂÂ1962, Sukhoi experimented with blown flaps on S-25 but the benefit was too small to warrant implementation. JATO rockets tested on S-22-4 proved more useful and were incorporated into the Su-7BKL. Attempts to improve takeoff and landing performance eventually resulted in the variable geometry Sukhoi Su-17.
The Su-7B and its variants became the main Soviet ground-attack aircraft of the 1960s. They were also widely exported (691 planes, including some trainers). However, the very short combat radius and need for long runways limited the Su-7's operational usefulness. On the other hand, despite its notoriously heavy controls, the Su-7 was popular with pilots for its docile flight characteristics, simple controls and considerable speed even at low altitudes. It also had a reputation for easy maintenance.
In 1977âÂÂ1986 the Su-7s remaining in Soviet service were replaced by Su-17s and MiG-27s.
The Su-7 saw combat with Egypt in the 1967 Six-Day War, the subsequent War of Attrition, and saw use in the Yom Kippur War by the Egyptians to attack Israeli ground forces.
The Indian Air Force (IAF) used the Su-7 extensively in the 1971 war with Pakistan. Six squadrons, totaling 140 aircraft, flew almost 1,500 offensive sorties during the war, and undertook the bulk of the daytime attack missions. The IAF managed to retain a very high operational tempo with its Su-7s, peaking at a sortie rate of six per pilot per day. Fourteen or nineteen Su-7s were lost during the war, mostly due to anti-aircraft fire. After the war, it was found that the aircraft had high survivability, being able to fly home safely despite receiving heavy damage. For example, Wing Commander H.S. Mangat's Su-7 was badly damaged by a PL-2 missile fired by a Pakistan Air Force F-6. The impact was so severe that half the rudder was missing, the elevators, ailerons, and flaps were severely damaged, and half the missile was stuck in the chute pipe. The pilot made it back to his base. The death of at least one Indian pilot can be attributed, at least indirectly, to poor cockpit design. A pilot had moved his seating forward to a dangerous position, "because he found the bombsight and the front gun sight easier to operate" while in that position and was killed on ejection.
Indian Su-7BMKs shot down at least two Shenyang F-6s in the 1971 war, while losing three Su-7s to F-6s according to Pakistani sources, mostly during bombing runs.
Syria and Iraq both received their first SU-7s from the Soviet Union in 1968, with the Syrians receiving 25 airframes in an initial batch followed by more purchases in the lead up to the 1973 Arab-Israeli war. These Su-7s were used intensively, primarily for ground attack and support missions and were valued for their supersonic performance and hard punch, and when the war broke out, the Syrian Air Force Command - let by Major General Najr Jamil - had about 80 Fitter-As ready for combat (not counting a number of Iraqi SU-7s also based in Syria at the time). SU-7s were used intensively and especially in low level attacks which the Israelis had a lot of trouble detecting and intercepting (in comparison to the MiG-21s flying top cover for the Fitters and MiG-17s). After the war, during which the Syrians suffered considerable losses, 35 SU-7s were supplied by the Russians as replacements or extra airframes, and they would be in Syrian service until the 1990s before being phased out.
A total of 1,847 Su-7 and its variants were built.