Russian defense company Rostec at the Eurasia Air Show 2018 evinced an intention to join the TF-X program[34][35]. In a surprise move, some Russian companies (United Engine Corporation) have also stated that they were ready to provide technology for the TF-X engine[36]. Turkish defense officials confirmed that they are exploring this option and discussing potential cooperation models. Turkish President Erdoğan, accompanied by Russian President Putin, were showcased the fifth-generation Sukhoi Su-57 stealth fighter jet at the MAKS 2019 international airshow in the Moscow region on 27 August 2019.[37]

일단 위 내용은 위키피디아 문서내용이긴한데 주석으로 달린 기사 링크들이 어느정도 말이 나오긴 했다는걸 증명하는걸지도?