Su-57 Felon.

The Su-57 Felon, developed under Russia’s PAK FA program, represents the country’s first stealth multirole fighter, designed to replace aging Soviet-era platforms like the MiG-29 and Su-27 in the Russian Aerospace Forces. Developed by Sukhoi, a key division within the United Aircraft Corporation (UAC), the project, originally codenamed Stolitsa (Capital City), brought together expertise from prominent Russian aerospace entities. In 2002, Alexander Davidenko was appointed T-50’s chief designer at Sukhoi, overseeing a collaborative effort with the Novosibirsk Aircraft Production Association (NAPO) and Komsomolsk-on-Amur Aircraft Production Association (KnAAZ), with final assembly at KnAAZ in Komsomolsk-on-Amur. This collaborative approach across multiple facilities helped accelerate development and ensure a broad base of technical input.

A consortium of Russian defense and aerospace firms crafted the aircraft's avionics suite, selected in 2003 after a rigorous competition. Tekhnokompleks Scientific and Production Center, the Ramenskoye Instrument Building Design Bureau, the Tikhomirov Scientific Research Institute of Instrument Design (NIIP), the Ural Optical and Mechanical Plant (UOMZ), Polet, and the Central Scientific Research Radio Engineering Institute in Moscow collectively contributed to the Su-57’s advanced sensor, radar, and electronic warfare (EW) capabilities. In parallel, NPO Lyulka-Saturn (now NPO Saturn) was contracted in 2004 to develop the AL-41F1 engines, designated as "Izdeliye 117" (Product 117), specifically engineered to deliver the power, thrust vectoring, and supercruise capabilities required for the Su-57’s combat profile.

To mitigate development risks and contain costs, Sukhoi used various prototype aircraft to test Su-57 components. The Su-47 airframe tested internal weapon bays, while Su-27M prototypes evaluated the flight control systems and engines. Sukhoi also integrated elements of the Su-57’s technology into an upgraded variant of the Su-27, which eventually entered service as the Su-35S in 2014, bridging the gap between fourth-generation fighters and the anticipated fifth-generation capabilities of the Su-57.

By December 2004, the conceptual design of the Su-57 was completed and received formal approval from Russia’s Ministry of Defense. Government funding increased significantly in 2006 to support the next stages, and by 2007, Russian military officials confirmed the aircraft was ready for construction, with flight testing of initial prototypes expected by 2009. The T-50 was officially re-designated the Su-57 in July 2017.

Russia also pursued international partnerships early in the PAK FA program to secure additional funding and long-term export orders. In 2007, Russia and India entered into a joint development agreement, with Hindustan Aeronautics Limited (HAL) collaborating with Sukhoi on a derivative known as the Fifth Generation Fighter Aircraft (FGFA). Although both countries initially committed significant funding, India later withdrew in 2018, citing concerns over cost, workshare, and perceived capability gaps.

Despite this setback, Sukhoi continued development of the Su-57 and increasingly promoted the aircraft to potential export customers. At the MAKS-2019 air show, the export variant, designated Su-57E, was unveiled and presented as Russia’s offering to the international market. The aircraft was later displayed at Airshow China 2024 in Zhuhai, marking its first official appearance at China’s premier aviation exhibition and highlighting Moscow’s efforts to attract foreign operators.

During the Zhuhai exhibition in November 2024, Russia’s state arms exporter Rosoboronexport announced that the Su-57E had secured its first international customer, while declining to identify the buyer. The announcement sparked considerable speculation, with Algeria widely regarded as a leading candidate because of its longstanding defense relationship with Russia and its ongoing efforts to modernize its combat aircraft fleet.

Algeria subsequently confirmed its acquisition of the Su-57E in February 2025 through an announcement broadcast on national television. Reports indicated that Algerian personnel were undergoing training in Russia and that deliveries of the aircraft were expected to begin thereafter, making Algeria the first publicly identified foreign operator of the Russian fifth-generation fighter.

- Su-57 (Baseline Variant): The original fifth-generation stealth multirole fighter developed by Sukhoi for the Russian Aerospace Forces. This variant focuses on air superiority, precision strike, and reconnaissance with advanced stealth and avionics capabilities.
- Su-57E (Export Variant): The Su-57E is an export-oriented version unveiled at the MAKS-2019 air show, intended to attract international buyers with capabilities tailored to comply with export restrictions while retaining core stealth and multirole functions.
- Su-57M (Upgraded Variant): An enhanced version of the Su-57 expected to incorporate the new Izdeliye 30 engines, which improve thrust, efficiency, and supercruise capabilities. This variant is also anticipated to feature advanced avionics and additional stealth improvements.
- Su-75 Checkmate (Single-Engine Variant): Although not a direct Su-57 variant, the Su-75 Checkmate is a light, single-engine fighter inspired by the Su-57’s design philosophy. Developed for affordability, ease of maintenance, and stealth, the Checkmate targets export markets and complements the heavier Su-57 platform.
- FGFA (Fifth Generation Fighter Aircraft): A proposed joint development between Russia and India based on the Su-57, also known as the FGFA. The project aimed to produce a customized version tailored to Indian requirements but was eventually canceled in 2018 due to performance concerns and cost issues.