2015 Russian Sukhoi Su-24 shootdown al-Nusra Front fighters. Russia has bombed the area near the Turkish border to support Syrian government forces. Syrian Turkmen formed their own armed brigades called Syrian Turkmen Brigades in opposition to the Syrian government of President Bashar al-Assad, loosely affiliated with other rebels such as the Free Syrian Army. The Turkmen brigades also cooperate with al-Qaeda's Syrian affiliate the al-Nusra Front and with the Salafi coalition known as Ahrar al-Sham. In Latakia the Turkish-supported rebels formed the Jabal al-Turkman Brigade. On 24 November 2015 at 9:24 am, as it was returning to Khmeimim airbase, a Russian Sukhoi Su-24 aircraft with
Sukhoi Su-57 produced, and some believe it to be an implicit announcement of the project's cancellation. The slowing of procurement could be because of the current slow growth of the Russian economy, while the future patches' procurement are for an unknown future; the Russian military could be waiting for the more powerful Saturn izdeliye 30 engine to be ready for serial production. On 22 August 2018, during the International Military-Technical Forum «ARMY-2018», the Russian Ministry of Defence and the JSC Sukhoi signed the first contract for delivery of two serial Su-57s. The contract should be finalized between 2018 and 2020. The prototype's