Russia’s Su-57 Stealth Fighter Program: An Overview

The Russian Air Force’s bold ambitions to operate a fleet of stealth fighter aircraft that would replace the majority of Soviet-era fighters by the late 2020 finally came crashing down in July 2018 when the Russian Ministry of Defense announced that the country’s first indigenously designed and built stealth fighter jet, the Sukhoi Su-57, will not enter serial production for the time being. While the announcement was long expected given budgetary constraints and various technical issues with the stealth fighter, it nonetheless constituted a severe blow to the Russian military aviation industry.

Instead of the Su-57, the Russian Air Force will continue to rely on its most advanced fourth-generation fighter jets, such as the MiG-29SMT Fulcrum and Sukhoi Su-35S Flanker-E, for the near future. Serial production of the Su-57 would only occur once the Russian Air Force’s legacy fighter aircraft lag behind their Western equivalents, according to Russian Deputy Defense Minister Yuri Borisov. The Su-57 will be “our trump, which we can always play when the aircrafts of previous generations will start to lag behind in capabilities when compared to similar aircraft from the world’s leading countries,” Borisov said in July.

However, not only is it highly uncertain whether Russia will have the necessary resources to reboot Su-57 production in a couple of years, but it is also doubtful whether the fifth-generation fighter jet, a multirole, single seat, twin-engine air superiority/deep air support fighter aircraft, will meet the operational requirements of the Russian Air Force by that time. So, does the July 2018 announcement mark the beginning of the end for the Su-57, which has been in development since the early 2000s under the PAK-FA fifth-generation fighter program?

It certainly looks like that is the case when it comes to the aircraft’s large-scale operational deployment. Undoubtedly, initial plans of the Russian Ministry of Defense to have 150 Su-57s in service by 2020 were always unrealistic. While this number was later revised down to 55 and eventually to 12, continuing technical challenges with the aircraft’s sensors, mission systems, low observable structure, and turbofan engines may make the production of just a dozen Su-57s difficult to achieve by the early 2020s. Indeed, according to Russian media reports, the actual number of aircraft delivered by the end of 2019 or 2020 could now be just two.

As of October 2018, it is thought that the Russian Air Force is operating 10 Su-57s prototypes for evaluation and testing, two of which deployed to Syria for a combat mission earlier this year. (The Su-57 conducted its maiden flight in 2010.) The performance of these prototypes, touted by senior Russian defense officials as some of the best aircraft produced in the world, has been seen as less impressive by India, Russia’s only international partner in the development of the aircraft.

Only two years ago India considered procuring over 140 fifth-generation aircraft from Russia. But the Indian government withdrew from the codevelopment and production of the Sukhoi/HAL Fifth Generation Fighter Aircraft (FGFA), also known in India as the Perspective Multirole Fighter (PMF), a stealth fighter aircraft to be based on the Su-57, in April of this year. The withdrawal was the result of a number of disagreements over cost sharing plans, technology transfers, and, most importantly, severe Indian doubts about the aircraft’s capability to meet Indian Air Force operational requirements.

“One of the IAF’s principal concerns included Russia’s failure to develop a next-generation engine for the FGFA to date,” I explained at the time. “Current prototypes of the aircraft are fitted with a derivative of the Russian-made Saturn AL-41F1S engine, dubbed AL-41F1, an older aircraft engine also installed on the Sukhoi Su-35S Flanker-E. A new engine — the Saturn Izdeliye 30 — purportedly capable of mounting 3D thrust vectoring nozzles, is not expected to be ready for serial production until at least 2020.”

India’s abandonment of the project after over a decade removed a critical source of outside funding. (Notably, problems with the aircraft’s engines continue to persist with the Su-57 prototypes.) It was India’s decision to pull out of the project that ultimately sank the last chance for the induction of Su-57s into service beyond the squadron level. Yet, while plans to field the aircraft in large numbers have been abandoned for now, it is still too early to write off the program as a complete failure.

The aircraft itself is a remarkable achievement for the Russian military aviation industry. It is the most advanced fighter jet that Russia has produced since the collapse of the Soviet Union and has specifically been designed with the Russian air warfare doctrine in mind, which emphasizes standoff capabilities.

It is worthwhile to reiterate that while the aircraft lacks high-end low observable design features, it was never meant to be a Russian version of the U.S.-made F-22. Russia knew from the beginning that it could never directly compete with the United States in that field. Nonetheless, the Su-57 has a number of features that will make it a formidable opponent, including an active electronically scanned array (AESA) X-band radar system, 101KS “Atoll” infrared search and track sensors for detecting and tracking stealth targets at a long distance, and advanced incoming missile detection and defense capabilities.

Besides, the aircraft is slated to be armed with some of the most advanced standoff weapons in Russia’s arsenal, including the R-37M ultra-long-range hypersonic missile and other beyond visual range air-to-air missiles, as well as air-to-ground missiles including the extended range Kh-35UE tactical cruise missile. These standoff weapons systems will allow the Su-57 to stay far enough away from threatening air defense systems to remain undetected, which, along with its supposed advanced electronic warfare capability, reduces the need for high-end low observable design features. 

Despite severe setbacks in the program, the Su-57 also serves a useful role as a technology testbed and a useful research and development tool for next-generation military aviation technology. For example, Russian defense officials have claimed that hardware elements designed for a future sixth-generation fighter have been tested on the Su-57, including mission systems as well as advanced electronic warfare and new radar systems, over the past two years. Russia revealed for the first time the design of a new sixth-generation fighter aircraft in 2016.

While the Russian military aviation industry has clearly failed in its mission to equip the Russian Air Force with an operational fifth-generation fighter aircraft on a large scale, the Su-57 program has nonetheless yielded some tangible benefits for future Russian air power and will continue to do so. It should also be noted that the program has not officially been cancelled and there could be new impetus to add additional Su-57s in the 2020s, depending how quickly and effectively current technological challenges – particularly when it comes to the aircraft’s engine – will be addressed.