Yugoslavia. On 22 November 1984, an Orao broke the sound barrier while in a shallow dive; this instance made the J-22 the first Yugoslav-designed aircraft to exceed Mach 1. The aircraft is incapable of breaking the sound barrier in level flight, so it is classified as being a subsonic aircraft. Design The J-22 Orao is a twin-engined combat jet aircraft designed for performing close air support (CAS), ground-attack and tactical reconnaissance missions, it also features a limited air-defense capability. The twin-seat version, the NJ-22, was primarily assigned for various training purposes, including the advanced flight and weapons training syllabuses, but could also be used for combat missions. The Orao was provisioned with standard communication and navigation equipment, the latter including a Honeywell-built SGP500 twin-gyroscope navigation system. It incorporated a fire control and weapons management system which used the Thomson-CSF-built VE-120T head-up display (HUD) (which had replacing the original Ferranti ISIS D-282 gyro-sight). In terms of defensive sensors and systems, it was equipped with an Iskra SO-1 radar warning receiver (RWR) and provision for up to three chaff/flare dispensers, as well as a P10-65-13 passive jammer pod. Further pods could be optionally fitted, including an optical/infrared reconnaissance pod or an optical reconnaissance/jammer pod. Various upgrade programmes for the J-22 had been proposed during the 1990s; reportedly, such efforts would have been focused upon the aircraft's avionics. However, such ambitions were heavily undermined by the dismantling of the Mostar factory during the Yugoslav Wars and the collapse of Romania's communist government. During the late 2010s, Serbia launched a major modernisation programme involving both its J-22 and NJ-22 fleets. Unofficially referred to as Orao 2.0, this work involved the installation of new navigation and targeting systems, including Safran's Sigma 95 inertial navigation system, a mission computer and multi-function displays, into the NJ-22's rear cockpit which, along with new weapons, is intended to make the type more effective in ground attack missions. A more comprehensive second phase is to achieve the "complete digitalisation" of the aircraft's cockpit. Operational history The first Yugoslav Air Force unit to receive the J-22 was the 351st reconnaissance aviation squadron of the 82nd Aviation Brigade, Cerklje. Until the 1991 war, . There were also about three squadrons partly equipped with J-22s. At the beginning of the Yugoslav wars, in Slovenia, J-22s flew over in a show of force, but did not drop any bombs. During 1991, the first offensive