The AI-25 was designed to power the Yakovlev Yak-40 tri-jet airliner, often called the first regional jet transport aircraft, and is the starting point for the Lotarev DV-2 turbofan engine. The project was launched in 1965, with the AI-25s first test flight in 1966, and finally cleared for production in 1967. In 1972, the AI-25 was selected for the PolishPZL M-15 Belphegor, the world's only jet-powered biplane. Development of the AI-25 continued and the uprated AI-25TL was designed for use by the CzechoslovakAero L-39 Albatrosmilitary trainer with the first flight occurring in 1968. The L-39, would go on to become one of the most popular, and widespread trainer aircraft in the world, with over 3,000 L-39s produced, and with 2,900 examples still in active service today. A smaller version of the AI-25TL, the AI-25TLK has equipped the People's Republic of ChinasHongdu L-11 fighter-trainer. The AI-25TLK is also licensed built in the People's Republic of China as the WS-11. Another variant of the AI-25, is the AI-25TLSh in the 1990s, which underwent flight testing by the Ukrainian Ministry of Defense in 2002. Ivchenko-Progress is currently marketing the AI-25TLSh as an upgrade to existing L-39 and JL-8 operators that would extend the service life of the aircraft and improve performance. The latest AI-25 is the AI-25TL Series 2 designed for the Mikoyan MiG-AT.