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*{{Cite book |last=Trevisan |first=Alberto |url=https://www.worldcat.org/oclc/1102383204 |title=Assaltatori ed aerei da attacco al suolo russi e sovietici: progetti, prototipi ed aerei operativi |date=2019 |publisher=IBN |others=Anatoly P. Borovik |isbn=978-88-7565-422-1 |location=Roma |language=Italian |oclc=1102383204}}
*{{Cite book |last=Trevisan |first=Alberto |url=https://www.worldcat.org/oclc/1102383204 |title=Assaltatori ed aerei da attacco al suolo russi e sovietici: progetti, prototipi ed aerei operativi |date=2019 |publisher=IBN |others=Anatoly P. Borovik |isbn=978-88-7565-422-1 |location=Roma |language=Italian |oclc=1102383204}}
Work on creating an attack aircraft to replace the Su-25 started in 1984, with the first project ready by 1989 called Sturmovik-90. One of the options developed in the Sukhoi Design Bureau received the T-12 index. It had an atypical layout. The plane had a fuselage body with two cabins between which the air intakes were located, with forward-swept wings. Electronic countermeasures pods were fitted on the wingtips. The pilot and the radar system would be located in the left cabin while a weapons system officer and an optronics targeting system were to be in the right cabin..
Armament was to be in two internal weapons bays, although it was possible to place additional weapons on pylons under the wings. Preparations for the manufacturing of the T-12 included an assembly line at Sukhoi's Irkutsk plant, but the dissolution of the Soviet Union put an end to the project.