Sukhoi Su-25UB / Su-25UBK
The two-seat combat trainer — a raised rear cockpit and nearly the full fighting capability · First flight 1985 · UBK export from 1986
The Su-25UB (Uchebno-Boyevoy, 'combat trainer') was drawn up in 1977, but the first prototype, T-8UB-1, was not rolled out until July 1985 and flew from the Ulan-Ude factory airfield on 12 August that year. Twenty-five had been built by the end of 1986, when the two-seater completed its state trials. Its performance is close to that of the single-seater and it keeps the nav-attack and weapons-control systems, so it serves both for conversion training and for live weapons training.
From 1986 to 1989 Ulan-Ude also built the Su-25UBK for countries that bought the Su-25K, with the same modifications as that aircraft. Bulgaria had three UBKs at Bezmer, Czechoslovakia's single UBK passed to the Czech Republic in 1993, and Slovakia's '3237' was sold to Armenia in 2004. North Macedonia flew one Su-25UB alongside three single-seaters until 2004.
The two-seat airframe produced several offshoots: the hook-equipped Su-25UTG, first flown in September 1988 to train pilots for the carrier Admiral Kuznetsov (about ten built), the Su-25T anti-tank aircraft, and the Su-25UBM combat-capable trainer, which first flew on 6 December 2008.
