Suchoj Su-20 [kód NATO: Fitter-C]

Sukhoi Su-20

Already at the beginning of the production Su-17M in 1972, the top party and state authorities of the USSR decided to produce its export variant. The project, initially called S-32MKI, later S-32MK - Su-20 was completed very quickly. As early as 15 December 1972, the aircraft made its first flight, using the first Su-17M of the 55th production series (5501) to build the first prototype. Before the first flight, it was introduced to interested parties from Egypt and later Iraq.
The Su-20 aircraft was fully equivalent to the Su-17M produced from the 63rd production series, i.e. with a payload capacity of 4000 kg and four under-fuselage hangers. The airframe systems, avionics and engine were also the same AL-21F3. The main difference was in the armament. The bomb armament was the same, including the MBD bundled hangers. Unguided rocket armament was limited to S-5 rockets in UB-32A rocket launchers and large caliber S-24 rockets. Instead of cannon containers SPPU-22, the aircraft could carry up to four containers UPK-23-250. In addition, anti-aircraft cruise missiles R-3S were introduced, and a radar rangefinder SRD-5M was installed in the engine air inlet cone. Other armament was not allowed to be exported.
The aircraft was produced in A and B variants. The A variant for the Warsaw Pact countries (ordered by Poland) came with the PBK-2KL sight for bombing from level flight and from climb, and the BD-57FNM hangers for carrying nuclear bombs. The B variant for third world countries was without the PBK sight and nuclear hangers, had a modified SRO-2 self-targeting recognition system and an older type of radio. Already after the end of deliveries after 1976, some Polish aircraft were modified to use the Complex Reconnaissance Container KKR-1 in the export variant (it had an older radar system). Supposedly, in 1979, the export of anti-ship cruise missiles Ch-23 was additionally allowed, but the Poles did not purchase them. The aircraft were further exported to Egypt, Syria and Iraq.
Between 1973 and 1976, a total of 138 aircraft were produced. However, for several years it was the last export aircraft equipped with the AL-21F3 engine. In 1976, the USSR Ministry of Aerospace Industry banned their export, due to the ramp-up of Su-24 production and problems with engine production. Only MiG-23BN, Su-22 and Su-22M fighter-bomber aircraft with R-29B-300 engines continued to appear in export offers. The ban was lifted in 1983.

Source:
Yefim Gordon, Dmitry Komissarov "Sukhoi Su-7/Su17", Midland Publishing 2011
Viktor Y. Markovskiy, Igor V. Prikhodchenko: Istrebitel-bombardier Su-17, Aviacia i kosmonavtika vchera, segodnya i zavtra No. 10/2011.

Výkres Su-20

In 1985, a pair of Su-20 aircraft originally belonging to the Egyptian Air Force arrived in Germany. The two aircraft received the German designations 98+61 and 98+62 and were tested by the WTD-61 unit in Manching. The 98+61, which you can see in the photo from the Berlin-Gatow Aviation Museum, has survived to this day. (©Radek Havelka)

The Polish specimen located at the gas station near the village of Broniszew.