The Kaliningrad K-5 (NATO reporting name AA-1 Alkali), also known as RS-1U or product ShM, was an early Soviet air-to-air missile.
== History == The development of the K-5 began in 1951. The first test firings were in 1953. It was tested (but not operationally carried) by the Yakovlev Yak-25. The weapon entered service as the Grushin/Tomashevich (Russian: Грушин/Томашевич) RS-2U (also known as the R-5MS or K-5MS) in 1957. The initial version was matched to the RP-2U (Izumrud-2) radar used on the MiG-17PFU, MiG-19PM. An improved variant, K-5M or RS-2US in PVO service, entered production in 1959, matched to the RP-9/RP-9U (TsD-30) radar of the Sukhoi Su-9. The People's Republic of China developed a copy under the designation PL-1, for use by their J-6A fighters. The difficulties associated with beam-riding guidance, particularly in a single-seat fighter aircraft, were substantial, making the 'Alkali' primarily a short-range anti-bomber missile. Around 1967 the K-5 was replaced by the K-55 (R-55 in service), which replaced the beam-riding seeker with the semi-active radar homing or infrared seekers of the K-13 (AA-2 'Atoll'). The weapon was 7.8 kg (17 lb) heavier than the K-5, but had a smaller 9.1 kg (20 lb) warhead. The K-55 remained in service until about 1977, probably being retired with the last of the Sukhoi Su-9 interceptors.
== Specifications (RS-2US / K-5MS) == Length: 2,500 mm (8 ft 2 in) Wingspan: 654 mm (2 ft 1.7 in) Diameter: 200 mm (7+7⁄8 in) Launch weight: 82.7 kg (182 lb) Speed: 800 m/s (2,880 km/h; 1,790 mph) Range: 2–6 km (1+1⁄4–3+3⁄4 mi) Guidance: beam riding Warhead: 13.0 kg (28.7 lb)
Operators
=== Current operator === North Korea Used on MiG-21PFM.
=== Former operators === Soviet Union Both the Soviet Air Force (VVS) and the Soviet Air Defence Forces (PVO) operated the K-5. Albania The Air Force of the Albanian People's Army received 400 PL-1 from China in 1965 and 1966 for its Shenyang F-5 (MiG-17F) aircraft Bulgaria Used by the Bulgarian Air Force as late as December 1984 China The People's Liberation Army Air Force operated licensed Chinese copy of Kaliningrad K-5 designated as PL-1 (PL: short for Pi Li or Pili, meaning thunderbolt). Cuba Used by the Cuban Revolutionary Air and Air Defense Force as late as December 1984 Czechoslovakia The Czechoslovak Air Force operated RS-2U and RS-2US. East Germany The Air Forces of the National People's Army operated RS-2U on MiG-19PMs and MiG-21PF. Hungary The Hungarian Air Force operated RS-2US on MiG-19PMs, MiG-21PFs and MiG-21MFs. Iraq Used by the Iraqi Air Force as late as December 1984 Mali Malian Air Force Poland The Polish Air Force operated RS-2US on MiG-19PMs and MiG-21s. Remained in service as late as December 1984 Romania Locally produced A-90 copy by Electromecanica Ploiesti (1984)
== See also == List of missiles
== References == Citations
Bibliography Cooper, Tom; Weinert, Peter; Hinz, Fabian; Lepko, Mark (2011). African MiGs, Volume 2: Madagascar to Zimbabwe. Houston: Harpia Publishing. ISBN 978-0-9825539-8-5. Gordon, Yefim (2004). Soviet/Russian Aircraft Weapons Since World War Two. Hinckley, England: Midland Publishing. ISBN 1-85780-188-1. International Institute for Strategic Studies (December 1984). Correll, John T (ed.). "The Military Balance 1984/85". Air Force Magazine. Vol. 67, no. 12. Arlington, Virginia: Air Force Association. ISSN 0730-6784. Retrieved 13 January 2026 – via Google Books.
External links
RS-2U - Air-to-Air missile at aviation.ru K-5 at airwar.ru (in Russian)K-5 Archived 2020-08-24 at the Wayback Machine at missiles.ru - Electromecanica website: Air-to-Air missile