Sukhoi Su-17 / Su-20 / Su-22 (Fitter)

History of Sukhoi Su-17/Su-20/Su-22 (Fitter)

The Mach 2-capable Sukhoi Su-17 "Fitter" is an evolution of the successful Su-7 "Fitter-A" fighter/fighter-bomber family, as detailed elsewhere on this page. The aircraft employs a partially variable geometry ("rotor") wing system that improves the former's take-off and landing characteristics, as well as the low-altitude performance required for ground attack operations. The swinging wing elements contribute to aircraft stability at low speeds and low altitudes, while improving overall range and ammunition loading through the use of large-area fixed-wing "gloves". In addition to the new wing layout, the Su-17 differs from the original Su-7 with a redesigned canopy and nose assembly and a recognizable raised fuselage spine, giving the new aircraft a thinner-than-pencil look.

Assemblers are more burly - one. This model served the Soviet Union well and was widely exported to Warsaw Pact countries and trusted third world allies. The Su-17 was developed into the export models Su-20 and Su-22 Fitter, with different avionics, engines and weapons. In total, some 2,867 Su-17/Su-20/Su-22 armament were produced, almost half of which were supplied to Soviet export customers. More than a dozen nations adopted this type and made it the primary fighter-bomber throughout the Cold War.

Some Air Forces are still flying the planenearly four decades after its launch.

Development-Installer-B

The Su-7 (NATO codename "Fitter-A") is a unique and capable aircraft. However, there are glaring flaws in its range -- no, thanks to a thirsty powerplant -- and its ordnance-carrying ability. Sukhoi and Soviet authorities sought further improvements to make the Fitter series a more powerful and versatile battlefield component. Therefore, the Su-7BM production model was used as a demonstrator for testing the newly developed variable-geometry swing-wing system.

The new wing basically consists of two parts - the fixed wing root/glove and the positional rotating wing section, which makes up half of the wing (about the middle of the span). The new prototype became the Su-7IG ("IG" stands for "Izmenyaemaya Geometriya", also the internal name for "S-22I"). The first flight took place on August 2, 1966.

The working prototype/technology demonstrator showed great promise in this testing phase, improving the Su-7's field performance and range, and was therefore selected for production.

The long-fuselage two-seat Su-7U trainer was subsequently modified. The rear instructor's cockpit will make room for additional avionics and fuel, while also accommodating new wing components. The rotor configuration is designed to increase the Su-7's inherent range while allowing the aircraft to carry more weapons along its fixed wing section without the need to install heavy and complex rotor weapon stations to maintain aerodynamic integrity in flight.

The limited edition came under the base name "Su-17" and was equipped with a Lyulka AL-7F-1 turbojet engine with a thrust of 22,046 pounds. This early Fitter-B was produced from 1969 to 1973.

The export version of this ground attack model became the Su-20. The Su-20 prototype flew for the first time on December 15, 1972. Egypt, Poland and Syria are the main export customers for the new aircraft. The Su-20R is an export reconnaissance aircraft equivalent to the baseline Su-20.

Assembler-D

The Su-17M2 was the next definitive development and received the NATO designation "Fitter-D". It is essentially an improved production form of the earlier model, known internally as the S-32M2 by Sukhoi.

The nose assembly has been lengthened by 15 inches and redesigned with more downward slope to improve the pilot's forward vision "outside the cockpit" - a plus for the low-pilot role. This new fitter also removes the ranging radar, but integrates the Fon-1400 laser rangefinder as well as additional combat-related avionics. The DISS-7 Doppler Navigation Radar was installed in the fairing under the nose, and the aircraft made its maiden flight on December 20, 1973.

Production began in 1974 and continued until 1977, with the Su-17M2 officially entering Soviet service in 1975. The Su-17M2 has a fixed impact cone.

The Su-17M2D is another Fitter-D development, but with the 25,335 lbf Tumansky R-29BS-300 production engine, in a modified rear fuselage (a distinguishing feature of the variant) and a shorter The fuselage is afterburning the overall hull. The power increase offered by this engine is small and limited in range, so it will only be available in upcoming export deliveries.

The first flight took place on January 31, 1975, and production continued from 1977 to 1978.

Fitter-E - Trainer

The Su-17UM is a two-seat trainer developed from the S-52U prototype, NATO codenamed "Fitter-E". Production began in 1976, the same year the aircraft entered service. Production continued until 1978.

The fuselage of the new aircraft has been modified lower to accommodate the addition of a second instructor cockpit. It also caused some internal fuel space to be wiped, reducing the aircraft's range. The avionics of the original production model were retained, while the port gun was omitted. A vertical tail was added to counteract the effects of longitudinal instability (at high angles of attack).

The first flight took place on August 15, 1975.

The two-seat Su-17UM, with export designation Su-22U, was equipped with Tumansky R-29 series engines.

Assembler F

Export model Su-17M2D became Su-22, belonging to Sukhoi designation S-32M2K. The Su-22 is equipped with the same K-36D ejection seat system as modern jets MiG-29 "Fulcrum" and Sukhoi Su-27 "Flanker" and is powered by Tumansky R-29 engines.

The Su-22 is also equipped with a fixed shock cone, laser rangefinder and Doppler radar.

Assembly-G

The Lyulka-powered Su-17UM3 (S-52UM3, NATO codename "Fitter-G") is an improved modified trainer with a deeper fuselage and an improved vertical stabilizer. It was installed in the Su-17M3 avionics kit and first flew on September 21, 1978. Production continued from 1978 to 1982.

Export form was offered as Su-22UM3 and Su-22UM-3K, each distinguished by the use of Tumansky R-29 and Lyulkin AL-21 series engines.

Assembler-H

The two-seat Su-17UM trainer airframe was also used in the development of the S-52 and became the Su-17M3 ("Fitter-H"). The coach's cockpit position is of course removed to make room for additional avionics and fuel storage, the latter of which is good for range.

Moved the Doppler radar outer fairing to the inner position and added provisions for AA-2 "Atoll" and AA-8 "Aphid" along the two attachment points below the wing guards. The first flight took place on June 30, 1976. Production continued from 1976 to 1981.

The Su-17M3 model (and related export derivatives) became the most numerous Su-17 fitter developments in the series, with nearly 1,000 examples produced in total.

Assembler-J

The downgraded export version of the Su-17M3 became the Su-22M ("Fitter-J", S-52K internal Sukhoi designation). The Su-22M prototype first flew on May 24, 1977, and production began in 1978 and continued until 1984. The improved export version was designated Su-22M3 (internal designation S-52MK).

Assembler-K

The Su-17M4 (internal designation S-54, NATO designation "Fitter-K") became the final production form of the Fitter. The first flight took place on June 19, 1980. Avionics have been significantly improved, the Su-17M4 is equipped with the SPO-15LE "Sirena" radar warning system, and the Lyulka AL-21F-3 engine. Engine cooling is addressed by implementing fuselage and tail mounted air intakes to promote better cooling airflow around the engine and nozzles, a key consideration for afterburning engines.

The shock cone is fixed in place and provides facilities to support anti-radiation and air-to-surface missiles. Production continued from 1981 to 1988.

Su-17M4 was offered to export customers under the designation Su-22M4 (internal designation S-54K). Production continued from 1983 to 1990. The Su-17M4 has a top speed of 1,155 mph (Mach 1.7) and an operational range of 715 miles (1,430 miles ferry).

Service is capped at 46,590 feet, while the rate of climb is listed as 45,275 feet per minute.

Modern export Su-22 assembly machine

The Su-22 series was later offered a modernization package, making these Fitters Su-22M5. The upgrade includes Russian- and French-based systems, including a new digital cockpit with hand throttle and stick (HOTAS), Phazotron/Thomson-CSF "Phathom" radar system, GPS navigation and an overall upgraded avionics suite, as well as Compatibility with TV and laser-guided munitions.

Israel's Lahav installed the Elta synthetic aperture radar system and new digital computer on the Polish Su-22.

Disposable Su-17 Fitter Evolutions

The Su-17 was also used in some "one-off" developments, which became the Su-17M-28 and Su-17MKG. The Su-17M-28 was used to test the AS-9 Kyle anti-radiation missile, while the Su-17MKG became the development platform for testing the AS-10 Karen and AS-14 Kedge. Air-to-surface missiles.

Both aircraft platforms are well suited to increase the overall lethality of the Su-17 Fitter family, particularly in its ability to successfully acquire and destroy ground targets.

Tour

To the casual observer, the Su-17 series is similar in appearance to the previous Su-7 series fitters. The most obvious change is the use of a swept fixed wing section to accommodate the pivot wing section of the wing assembly.

This will allow the new Su-17 to carry more ammunition around its center of gravity, while leaving the rest of the wings free to perform various expected flight maneuvers (takeoff/landing/low power flight) for better range and performance, to provide cruise and high performance flight). The wing pivot positions are set to 28, 45 and 62 degrees respectively.

The wings are mounted low, with a slight dihedral (downward slope) along the cylindrical fuselage, and are fitted with a pair of large boundary layer fences extending longitudinally from the leading edge to the trailing edge (the fence is attached to the static section instead of cantilever wing section).

The fuselage features a truncated nose assembly that houses a full impact cone. Air is drawn in through air intakes mounted in the nose and around the impact cone, feeding a single engine buried in the fuselage. The pilot's seating position is very forward in the design, giving him a clear view of what's going on from all sides, except for the stern section, which is blocked by the raised fuselage spine. The spine extends from the rear of the base of the canopy to the base of a single vertical caudal fin overhanging the tail. The rear wing features a large swept horizontal stabilizer that complements the swept wing handguards and vertical stabilizer.

The horizontal plane spans both sides of a single engine exhaust ring. The landing gear (retaining the original Su-7 design) is fully retractable, consisting of two main landing gear struts (retracted inward towards the centerline) and a nose gear strut (retracted forward).

Armed

Standard armament (Su-17M4) is a pair of 30mm Nudel'man-Rikhter NR-30 series cannons (80 rounds per gun). The Fitter has a total of 12 hardpoints (in later production models) that can accommodate various air-to-air and air-to-ground mounts (two underwing hardpoints for air-to-air self-defense missiles), while four attachment points Located on the side of the lower part of the fuselage, three attachment points are located in each glove area on the underside of the wing). In air-to-surface missions, Fitter has been approved to carry AS-7 "Kerry", AS-10 "Karen", AS-11 "Kilter", AS-12 "Kegler" and AS-14 "Kedge".

Air-to-surface missiles , as well as conventional throwing bombs, laser-guided/photoelectric bombs, napalm, parachute bombs, cluster bombs, cannon pods (crossable GSh UPK-23 and GSh SPPU-22) and rocket pods. Fitter is authorized to carry AA-2 "Atoll", AA-8 "Aphid" and AA-11 "Archer" air-to-air missiles (primarily for self-defense).

External weapons are limited to 8,820 lbs.