On December 24, 2019 a Su-57 aircraft crashed some 120km from the Komsomolsk-on-Amur aircraft plant in the Far East Khabarovsk Krai region of Russia during a flight test. The pilot of the aircraft, that was participating in factory trials before delivery when the accident occurred, escaped without injuries and was rescued by a Mi-8 helicopter. It is claimed that the aircraft involved in the incident was the first serially produced Su-57. This is the first known loss of the Su-57, two of which were expected to enter the service of the Russian Air Force by the end of 2019 and two more in 2020. According to Russian media, despite the Su-57 crash the Russian Air Force is still expected to receive the first batch of serially produced Su-57 fighter jets in 2020. 

Designed by Sukhoi, the Su-57 (formerly T-50 and PAK FA) is a fifth-generation single seat, twin-engine multi-role fighter aircraft intended to be the successor to the MiG-29 and Su-27 in the Russian Air Force. The Su-57, recently codenamed the “Felon” by NATO, is the first indigenous combat aircraft program that was started by the Russian Federation and will be the first aircraft in Russian military service to use stealth technology. In August 2017, Sukhoi revealed that the T-50 PAK FA fifth-generation fighter jet had received the serial index of ‘Su-57’. Categorized as a ‘5th Generation Fighter’ the Su-57 is planned to have super cruise capability, stealth/radar-absorbing materials, supermanoeuvrability, networking, data fusion and advanced avionics. The Su-57 has been experiencing technical problems which caused delays in the program schedule. 

The first flight of the Su-57 took place on January 29, 2010 at Komsomolsk-on-Amur aircraft plant and according to Russian media there are a total of 13 Su-57 prototypes (10 for flight-tests plus 2 for static tests and one for ground tests). The 10th prototype (T-50-10) performed its maiden flight on December 23, 2017. Prototype aircraft are being used under the Su-57 Flight Test Program. In 2018, the first contract was signed for the delivery of an initial production lot (covering 12 aircraft) of Su-57 fighters to the Russian Ministry of Defence (MoD).  A second order, for a large batch (covering 76 aircraft) of Su-57s was placed by the Russian MoD in June 2019.

The prototypes and the initial production batch will be delivered with NPO Saturn AL-41F1 (Izdeliye-117) engines, closely related to the Saturn 117S engines used on the Su-35S, as interim engines while a new clean-sheet design Product 30 turbofan engine (Izdeliye-30) is currently under development. Each of the NPO Saturn AL-41F1/Izdeliye-117 turbofans provides 33,067lbs of thrust. According to Russian sources, though the AL-41F1 provides enough thrust for sustained supersonic cruise capability, however it does not meet the Russian Aerospace Forces requirements for thrust-to-weight ratio or fuel efficiency. On June 10, 2014, the fifth flying prototype, the aircraft T-50-5, was severely damaged by an engine fire after landing. The pilot managed to escape unharmed. The first successful test flight with a Su-57 (T-50-2 prototype) using the new generation Izdeliye-30 turbofan engine took place on December 5, 2017 and lasted 17 minutes. But the Saturn Izdeliye-30 is not ready for serial production. It is unclear when production will shift to the Saturn Izdeliye-30 engine. The new engine features increased thrust and fuel efficiency and is reportedly fitted with 3D thrust vectoring nozzles.

In May 2019 during a visit to the United Aircraft Corporation (UAC) Komsomolk-on-Amur aircraft plant in the Russian Far East, Russian Deputy Defence Minister Alexey KRIVORUCHKO had noted that the first Su-57 would be delivered to the Russian Air Force by the end of 2019. “We will get the first fighter jet (of this model) by the end of this year,” KRIVORUCHKO was quoted as saying by TASS news agency on May 29. “We are already talking about serial production. We have assessed the jet’s readiness today, as well as the plant’s readiness to mass manufacture the Su-57.  We were fully satisfied with what we saw and hope that all plans will be fulfilled.” The Russian Air Force was expected to receive two Su-57s by the end of 2019 and two more aircraft in 2020. 

In May, Russian President Vladimir PUTIN, however, announced that the Russian Air Force will procure a total of 76 Su-57s by 2028. In May 2019, Russian Minister of Defence Sergei SHOIGU also reported that the unit cost of each Su-57 and associated equipment went down by 20%. Russian Minister of Industry Denis MANTUROV told reporters on June 27, 2019 at the Army 2019 Forum that the Russian Ministry of Defence will receive 76 Su-57 jets within the framework of a contract with Sukhoi Company. In July 2019 Sukhoi commenced serial production of the Su-57 aircraft. According to Russian media the cost of the contract is estimated at around US$2.7 Billion. That works out to about US$35.5 million for each 76 Su-57 aircraft. The Su-57 fighter jets will be supplied by 2028, Russian Deputy Defence Minister Alexei KRIVORUCHKO told reporters.

Russia had deployed four Sukhoi Su-57 5th Generation fighter jets in Syria at the Khmeimim Air Base during first half of 2018 (in February) for combat-testing (operational and combat trials) purposes. The first pair (T-50-9 and T-50-11) arrived on February 21, 2018 and the second pair arrived on February 23. Meanwhile the Chief of Staff of the Russian Armed Forces, First Deputy Defence Minister General Valery GERASIMOV, stated in December that the Su-57, has undergone a “second combat testing” in Syria “during which all tasks planned were successfully performed.” The aircraft first participated in combat missions in Syria in early 2018.

The Russian Government has been in search for an export customer for the export version of its Su-57 stealth fighter dubbed the Su-57E. According to reports Algeria signed a contract to acquire 14 Su-57E 5th Generation fighter jets and became the first customer of this type. The Algerian Air Force has also signed two other contracts for 14 Su-34 bombers and 14 Su-35 air domination devices. Deliveries under the US$6 Billion contract would be completed by 2025. It is said that the purchase decision was made after the Algerian delegation visited the MAKS 2019 Air Show in the summer of 2019.