Vetrov-Kazakov VeK-20

The Vetrov and Kazakov VeK-20 (Stasnovan: Ветров-Казаков ВеК-20) is a Stasnovan supersonic fighter jet-interceptor designed by the Vetrov-Kazakov Design Bureau and based on the Gorbatovic not!MiG-21. Initial intent to purchase a license to built the Gorbatovic fighter in Stasnov was sidelined by different operational requirements put forward by the Stasnovan Revolutionary Air Force. As such the Gorbatovic design was adopted and then redesigned with an underslung intake, which freed up space for a larger radar dome and subsequently a more powerful radar. Later variants also featured canards and expanded wing area.

Origins and development
The VeK-20 was originally the designation given to a MiG-19-derived design in 1956, but that was later scrapped in 1958 favour of purchasing the Gorbatovic not!MiG-21, then in development. However, different requirements put forward by the Stasnovan Revolutionary Air Force development committee. Most important of those, the requirements called for the ability to mount a larger radars for PVO use, with the aim being to eventually be possible for the fighter to carry long-range SAHR missiles. As such, the VeK OKB was tasked of converting the Gorbatovic design to suit Stasnovan needs. The intake was moved to under to fuselage, and the shock cone was replaced with a conventional radome.

Initial production and prototypes - First generation

 * Os-2: Initial prototype variant, featuring a swept wing design
 * Os-3: Prototype with side mounted intakes.
 * Os-4: Prototype that was chosen for production. Featured a large ventral fin.
 * VeK-20: Initial production variant, with the ventral fin made smaller and vertical stabliser expanded.
 * VeK-20P: Introduced in early 1962 for PVO use, featured the more advanced RP-21 radar.

Further upgrades and specialised variants - Second Generation

 * VeK-20S: Introduced in 1964, featured the RP-22 radar that allowed it to carry K-8 SAHR missiles, two additional underwing hardpoints and a more powerful engine.
 * VeK-20U: Two-seat conversion trainer variant.
 * VeK-20SE: Export variant of the VeK-20S for Vastava Pact states with small changes to the IFF system. The VeK-20SK was offered to non-VP states, and featured a downgraded radar and engine.
 * VeK-20R: Recon variant featuring a Type D daylight PHOTINT pod, a Type N nighttime PHOTINT pod, a Type R general-purpose ELINT pod or a Type T pod housing a TV system. Entered service in 1966.

Modernisation - Third Generation

 * VeK-20M: Modernised variant that entered service in 1969 and featured forward canards for increased stability and agility, the RP-23 radar, also carried by the then-new VeK-24, a considerably upgraded avionics package and the capability to use R-4 SAHR AAMs.
 * VeK-20ME: Export variant of the VeK-20M for the Vastava Pact. The VeK-20MK subvariant was offered to non-VP customers, and had a downgraded radar and avionics package.
 * VeK-20UB: Two-seat conversion trainer variant based on the VeK-20M.
 * VeK-20MT: Entered service in 1971, upgrade with a larger spinal fuel tank and improved ground-attack capability.
 * VeK-20ML: The ultimate VeK-20 upgrade, entered service in 1976. It featured an expanded compound delta wing configuration with wingtip hardpoints, the RP-3ML radar with the capability to use R-23 long-range SAHR/IR missiles, and overall upgraded avionics package and a more powerful engine.
 * VeK-20MLE: Export variant of the VeK-20ML for VP countries. The non-VP export subvariant was the VeK-20MLK, with downgraded radar and avionics.

Upgrade programmes

 * VeK-20-94: Upgrade package for late model VeK-20s offered since the 90s. This includes and overall upgraded avionics package, a smaller version of the pulse-doppler rardar used on the VeK-29 which enables the aircraft to use modern ordnance such as R-77 AAMs and percision ground attack munitions. Additionally, the upgrade includes a dual-screen HUD, helmet-mounted target designator and advanced flight control systems.

Granzerian Variants

 * Juhasz J-5: Introduced in 1965, the first Granzerian domestically produced VeK-20 based on the initial production VeK-20 with the Stasnovan radar replaced by a Granzerian TBA radar. The aircraft was intended to replace the existing Juhasz J-2 in Granzerian service. These were armed with IÖR 58M infrared missiles and LÖR 58M semi-active radar missiles.
 * Juhasz J-6: Introduced in 1971, an upgrade similar to the Stasnovan VeK-20M, with forward canards and an improved radar and avionics.
 * Vertega V-7: Introduced in 1973 as the final Granzerian upgrade, the V-8 improved its radar and avionics and replaced the old LÖR 58M radar missiles with Vazandian missiles. This variant remained in Granzerian service until the mid 1980s.

Operators

 * Stasnov: While not in active service in Stasnov, the Revolutionary Air Force maintains an unspecified number of late-model VeK-20s in long term storage. Some are retained in operational status and used for air shows.
 * Granzery: The Granzerian airforce retains one fully operational Vertega V-7 aircraft as a museum piece.
 * Ziridava: The Ziridava People's Air Force operated numerous VeK-20SE and MLEs, some of which were lost during the Second Ziridavan Civil War. After the war, they continued to serve with the Republic of Ziridava Air Force, until they were all retired in 2005.