Vertega V221

The Vertega V221 Vipera (Granzerian: "Viper") was a twin-engine single-seat Second Great War turbojet fighter aircraft used by the Granzerian Royal Air Force in 1946–1947 and the Granzerian People's Air Force from 1947-1965. It was designed and built in Csongrád by Vertega. The Vertega V221 was the first combat jet aircraft to incorporate a design, and was one of the fastest jet aircraft developed during the War.

Design and development
The Granzerian Máté-Pétér S.1 experimental jet aircraft (which was in fact a pulsejet rather than a true turbojet) was the first Granzerian jet aircraft to fly, birthing the jet age for Granzerian Aerospace in 1940. Immediately afterwards the Granzerian firm Vertega bought the rights to the design of the S.1 and began to develop a pulsejet powered fighter aircraft called the Vertega V150, this was cancelled with the outbreak of the first Great War, as the pulsejet design was found to simply have insufficient power to be useful as a fighter aircraft.

Simultaneously, the Pokol Corporation had been exploring the idea of a turbo-prop powered combat aircraft, which would ultimately result in the heavy fighter. With both of these the Granzerian jet industry was one of the most developed in the world, and in 1940 the Werner Kraftwerk Iparag Corporation developed the WKW 004M turbojet for production in 1941, and the plans for an advanced jet fighter began. The development time of the V221 was exceptionally long for an aircraft of the war, but due to multiple setbacks with the airframe and engine, as well as repeated issues with the wing structure resulted in multiple delays, and the aircraft slated for introduction in 1944 was not finished for another two years. The wing was also the first on a major combat aircraft to incorporate an anhedral wing angle (1.5°), which traded stability in flight for manoeuvrability, which resulted in an aircraft that while considered difficult to fly was also surprisingly nimble for its speed.

Ultimately in 1945 the V221 had the wing structure completely redesigned following lessons learned from the poor performance of the Vertega V210 at maximum speed led to the development of the V221s signature swept-wing design, which would increase max speed and also greatly decrease the coefficient of drag at high speed. This resulted, alongside the tuned and refined version of the WKW 004M, the WKW 00R4M, in an aircraft which was the fastest in Atlas at the time of its inception, with what was described as "smooth" handling even at high speeds. A modified V221 was also the first Granzerian aircraft to break the sound barrier in 1951.

Operational History
At the time of its introduction in mid 1946, the V221 outclassed all other Allied jets it faced in the air, boasting a 5:1 kill-loss record with the and an astonishing 15:1 kill-loss record against the Stasnovan. As the war progressed and the V221 began to face against more sophisticated allied jet aircraft such as the, it found itself on more or less even footing, after the war Granzerian records claimed that the V221 when facing the VeK-9 in combat over Elesar and Granzery had shot down 107 VeK-9s for the loss of 83 V221s.

Post-War
At the conclusion of the Second Great War, the V221 remained in production as the primary fighter of Granzery as the Juhasz J-1 until the introduction of the Juhasz J-2 in 1959. The design of the V221 also inspired a generation of Stasnovan jet aircraft to follow such as the  and, which incorporated its revolutionary engine and wing designs. The Granzerian airforce continued to use the V221 as a trainer until the late 1960s, and a number remain in operational conditions as museum aircraft.

A Modified Granzerian V221 was used by Szabolcs Kollányi to break the sound barrier in 1952, the first Granzerian-built aircraft to break the sound barrier.