The Yakovlev Yak-23 (; USAF/DoD reporting name Type 28, NATO reporting name Flora) was an early Soviet jet fighter with a straight wing. It was developed from the Yak-17 in the late 1940s and used a reverse-engineered copy of a British engine. It was not built in large numbers as it was inferior in performance to the swept-wing Mikoyan-Gurevich MiG-15. Many Yak-23s were exported to the Warsaw Pact nations and remained in service for most of the 1950s, although some were still in use a decade later. Development and description On 11 March 1947, the Council of People's Commissars ordered several design bureaux (OKB), including that of Alexander Yakovlev, to develop a single-seat, straight-winged jet fighter to be equipped with a single British Rolls-Royce Nene or Rolls-Royce Derwent turbojet engine. The aircraft should have a maximum speed of at sea level and a speed of at an altitude of . It should be able to climb to that altitude in 3.5 minutes or less and should have a maximum range of no less than . Alexander Yakovlev decided to develop two designs, the Yakovlev Yak-25 in accordance with the Ministry's order and a lightweight, more agile aircraft (the Yak-23) in the hopes that one or the other would win an order from the Ministry. Yakovlev's decision was a risky one as it could be construed as unauthorized use of state monies if discovered, which could have landed Yakovlev in a lot of trouble. To minimize risk, the new aircraft used the same "pod-and-boom" layout as the earlier Yak-17 fighter, but the metal fuselage was redesigned as a semi-monocoque structure with the single-seat, unpressurized cockpit and its teardrop-shaped canopy positioned just above the trailing edge of the wing. Not coincidentally, this was also above the exhaust of the centrifugal-flow Klimov RD-500 engine, an unlicensed copy of the Derwent V. Fitted with tricycle landing gear, the main landing gear retracted inwards into the fuselage while the nose gear retracted forwards. Unlike the installation in the Yak-17, the Yak-23's forward landing gear was flush with the fuselage when retracted. The laminar-flow, two-spar, wing was mounted in the middle of the fuselage. It was equipped with slotted flaps and ailerons and had a modest 3° 30' dihedral. The horizontal stabilizers had 5° of dihedral. The pilot was protected by a bulletproof windscreen and the armored back of the ejection seat. The Yak-23 was equipped