The first prototype of the Iranian Kowsar-88 basic jet trainer made its first flight at the Islamic Republic of Iran Air Force‘s (IRIAF’s) Third Tactical Fighter Base at Hamedan (also known as the Martyr Nojeh base), most probably on October 15. Apparently renamed as the Yasin, the aircraft was formally unveiled on October 16 in a ceremony attended by Iran’s defense minister, Brigadier General Ali Hatami, Commander of the Air Force, Brigadier General (pilot) Nasirzadeh, and Vice President for Science and Technology, Surena Stari.
Designed by the Iran Aviation Industries Organization’s Aerospace Research Centre, the aircraft incorporates a number of lessons learned from the failed Ya-Hossein advanced-trainer project, under which Owj produced a succession of designs, starting with the Dorna (Lark), then the Tondar (Thunder), and finally the Tazarv (Pheasant). Many of the Owj Complex engineers and technicians were transferred to the Iran Aircraft Manufacturing Industries Corporation (IAMI, but better known by its Persian acronym, HESA), which was to be responsible for the new program.
Conceptual design of the Kowsar-88 (also known as the Kosar 88) began In December 2007, and resulted in a twin-engine aircraft that bears a passing resemblance to the Taiwanese AIDC AT-3 and the Mikoyan MiG-AT. The program was officially announced in 2013. The aircraft was designed to make maximum use of components from retired Northrop F-5A/B Freedom Fighters, including avionics and hydraulics systems, landing gear, and engines. This promised to reduce program costs and to overcome some of the problems posed by international sanctions. For the first batch of aircraft, the Iranian Air Force provided three RF-5As and six F-5As as donor airframes, and promised to add six two-seat F-5Bs.
Officially, the aircraft is powered by two J90 turbofans, which are described as locally manufactured, reverse-engineered derivatives of the General Electric J85, as used in the F-5A. It seems likely that refurbished J85s are actually installed. There are plans that they may be replaced in the 50 production Yasins by 100 Russian-supplied Salyut AI-222-25F engines, following an agreement signed at the MAKS show in 2017. Plans to equip the aircraft with glass cockpits—each with a HUD, three large MFDs and HOTAS controls—were abandoned when the Chinese contractor involved was deterred by the UN sanctions against Iran.
Work on the construction of the Kowsar-88 prototype began in 2016 after an Iranian request for the procurement of 24 Yak-130 advanced jet trainers was turned down. Originally the aircraft was scheduled to fly in February 2017, but the allocated engines were used in the Qaher F-313 mock-up, and the aircraft was still incomplete when it was unveiled in Tehran on April 15, 2017 and the first flight date slipped to mid-2018. Fast-taxi trials began in April 2018, but the aircraft was not ready in time for its planned debut in August 2018. Instead, a rebuilt Northrop F-5F Azarakhsh II that had been used as an avionics testbed for the Kowsar-88 was unveiled as though it was the ‘Kowsar-1’, leading to a great deal of confusion.
The IRIAF plans to procure 50 production Kowsar-88s as advanced jet trainers and light attack aircraft, with service entry provisionally scheduled for 2023. A 16-aircraft squadron will serve alongside the existing fleet of 11 modernized F-5B Simorghs. If sanctions are withdrawn, Iran plans to procure 24 Yak-130s, and if this happens, the Simorghs will be retired and used as donor airframes for 11 more Kowsar-88s.