Russia’s Sukhoi Su-57 is one of only four operational 5th generation fighters anywhere on the planet, keeping the rare company of China’s Chengdu J-20 and America’s Lockheed Martin F-22 and F-35. Each of these fighters was developed with different specialties in mind, but share a collective focus on a few specific design elements that have come to define their generation of aircraft, including stealth and data fusion capabilities.
There’s little doubt that America’s stealth fighters are the best in the world, with China continuing work on the WS-15 engine they believe will bring the J-20 on par with America’s dogfighting champion, the F-22 Raptor. The F-35 Joint Strike Fighter, on the other hand, isn’t an acrobatic prize fighter like the F-22, nor is it a long-range interceptor like the J-20. It is, however, an incredibly sneaky flying supercomputer that can make other platforms in the area more lethal through its presence. Russia’s Su-57 is widely seen as the least stealthy of the 5th generation entrants, but there’s more to a fighter jet than radar cross-sections.
Comparing these jets to one another in a head-on way doesn’t really do any of them justice, as none were intended to operate alone in contested airspace full of opposing fighters. Each of these platforms was developed to fill a role within a broader force structure and strategy, and as such, are unlikely to run across one another one-on-one in even the most dramatic of scenarios. Of course, that doesn’t mean we can’t compare these fighters on paper, it just means that which fighter would win in a Top Gun-style dogfight isn’t quite as important as which offers a greater jump in capability for the forces it supports.
All that is to say that, the Su-57 might just be the worst 5th generation fighter on the planet… but that doesn’t make it a bad fighter at all.
PAK FA: The troubled beginnings of the Su-57
The long road to the first Su-57 taking to the skies began in 1979 under the former Soviet Union, with plans to field a next-generation fighter that could enter service in the 1990s. However, the collapse of the Soviet Union in 1991 practically halted progress on the program, leaving America’s F-22 Raptor to claim the title of first stealth fighter unopposed with its first flight in 1997. Real development on the modern fighter program began once again in earnest in 2002, with America’s F-22 set squarely in the program’s sights.
By 2007, Russia’s PAK FA program, which was short for “‘prospective aeronautical complex of front-line air forces” in Russian, was once again steaming toward fielding a real stealth fighter. India, keen to have their own 5th generation aircraft, agreed to team up with the Russians to continue development and begin procuring what would eventually become the Su-57, but the partnership wasn’t to last.
In 2018, the Indian government signaled their departure from the program despite Russia’s promising claims about their first batch of prototype fighters, and while India’s official reasons didn’t suggest problems with the program itself, unofficially, rumors swirled that India had given up the PAK FA program because the fighter it produced simply wasn’t stealthy enough to survive in highly contested airspace, alongside a list of other concerns.
Nonetheless, Russia persevered. A total of 12 prototype Su-57s were constructed for testing and assessment, and just months after India backed out of the program, Russia’s Defence Ministry signed a contract to purchase the first two serial production Su-57s, slated for delivery in 2019 and 2020. Russia had already placed their prototype fighters in “operational service,” deploying them to Syria for little more than headline fodder and a few promotional photos, but these first two production jets were to be something more: They would not only represent Russia’s top-of-the-line fighters, they would be the nation’s first-ever production stealth aircraft.
The first production Su-57 crashed before it could even be delivered
In December of 2019, just days before the Russian military expected to receive their first serial production Su-57, the program was met with yet another dramatic setback. Sukhoi, the firm tasked with developing the Su-57, was conducting flight testing with the fighter to ensure it met the requirements for delivery when the aircraft crashed just 111 kilometers from the airfield it departed from.
The pilot, a civilian contracted with Sukhoi, ejected and survived, but the aircraft was a total loss. In the days that followed the crash, Russian investigators would cite a failure of the tail’s control surfaces for the incident, limiting the pilot’s ability to control the aircraft. According to Russian media outlets, the aircraft exploded upon impact with the ground.
It was a significant setback for a fighter program that had already spanned nearly five decades in its various iterations and a huge blow to Russia’s fragile reputation as a global military power. Shortly after the crash, Igar Ozar, the CEO of Sukhoi, resigned from his position.
That wasn’t the fighter’s only issue with production
One crash isn’t the extent of the Su-57’s production woes, however. The Russian government still projects to receive as many as 76 of the stealth fighter this decade, but while they were intended to field an advanced engine system designed specifically for the aircraft’s stealth role, delays in the engine’s development have hindered progress. It’s now expected that each Su-57 delivered to the Russian Air Force for the foreseeable future will come fitted with the Saturn AL-41F1 engine also found in the 4th generation Su-35S.
Not only does operating an older engine limit the performance of the Su-57, it also has a detrimental effect on stealth. Contrary to popular understanding, stealth isn’t a single technology or piece of equipment, but is rather a variety of overlapping technologies, production methodologies, and combat tactics. Defeating detection and weapons lock isn’t just about radar, it’s also about infrared heat signature–and the 4th generation engines designed for non-stealth aircraft employed in the Su-57 aren’t good at masking either.
And it’s not just with stealth and propulsion that the Su-57 continues to lag behind the competition. One of the aircraft’s selling points has also been its sensor suite and advanced avionics — with the Russian government claiming the fighter is capable of full 360-degree sensor coverage much like the flying supercomputer F-35 Joint Strike Fighter. To date, it does not appear that any such system is online in the Su-57, with the Rand Corporation analysis positing that sanctions placed on Russia after its military annexation of Crimean in 2014 have further hindered the system’s development.
What is the Su-57 really capable of?
It’s always difficult to divine real combat capability when analyzing programs like the Su-57. It’s difficult enough with a program like the F-35, which benefits from a concerted marketing campaign aimed at keeping the taxpayer happy with their investment and presenting the aircraft as a worthwhile purchase for foreign allies. It’s even more complicated in a nation like Russia, where news media is strictly controlled by the government. As a result, what we know for sure about the Su-57 and its capabilities is a shorter list than what we’re pretty confident about through analysis of open-source information, news reports, images, and video of the aircraft.
That is to say that any concrete breakdown of the Su-57’s capabilities should be taken with a grain of salt. Those who claim to know for sure what the aircraft can do are relaying numbers and data provided to the public by Sukhoi by way of the Russian government–who, like the United States, is counting on foreign sales of the fighter to offset the high cost of the plane’s development and production. In other words, Russia has at least two motives to present the Su-57 as more capable than it is: to present an image of military might in the face of Western opposition, and to entice potential buyers who want a stealth fighter but aren’t allowed (or can’t afford) to pursue the F-35.
But despite the marketing smokescreen, there are a number of things we can glean about the Su-57 and its capabilities.
It’s ranked last for stealth
While exact figures regarding the radar cross-section of the Su-57 aren’t available, the aircraft’s design is indeed stealthy… but stealth isn’t something you have or don’t have, it’s really more like a spectrum. Aircraft can be stealthier or less stealthy than others based on a variety of variables ranging from production tolerances in the fuselage construction to the direction from which they’re being observed. The Su-57’s stealth is hampered by Russia’s struggle to bond body panels of the aircraft as tightly as necessary to inhibit a radar return and by its modified 4th generation engines.
The Su-57 ranks last in stealth among its 5th generation counterparts, but that doesn’t mean its stealth capabilities should be utterly dismissed. Again, in combat, it’s not about whose fighter has the smallest radar cross section or infrared signature, it’s about leveraging these platforms for maximum effect, and the Su-57 wasn’t designed to serve as stealthy scrapper like the F-22.
As aviation expert and Defense Editor for Aviation Week Steve Trimble once explained to me, the Russian affinity for stealth isn’t as powerful as America’s, and as such, they aren’t looking to win the stealth competition. Instead, they’re just trying to make the Su-57 a sneaky and capable fighter with bombing capabilities… and in that regard, they seem to be succeeding.
Its avionics are headed in the right direction
It remains unclear just how far along the Su-57’s avionics suite truly is, but Russian officials have repeatedly drawn parallels between its ability to fuse data from a variety of sensors and the F-35’s game-changing degree of situational awareness. While the full sensor suite does not appear to be operational yet, industry publications have pointed to the Russian use of open system architecture and dispersed computing within the aircraft as strong indicators that the systems aboard the Su-57 are not only advanced, they’re upgradeable.
The Su-57’s cheek-mounted radars, nose-mounted X-Band N036 Byelka (Squirrel) AESA radar system, and 101KS ‘Atoll’ infrared search and track sensor give the fighter a great field of view and everything it might need to identify even stealthy opponents on the horizon.
It’s got speed and acrobatics
The Su-57 may not be the stealthiest or most technologically advanced 5th generation fighter on the market, but it’s still a product of Russia’s long and storied history of developing highly capable combat airframes. The same firm responsible for the Su-57 also produces incredibly capable 4th generation fighters like the Su-35, so it comes as little surprise that Russia’s first stealth fighter is no slouch in acrobatic performance.
The Su-57’s 3D thrust vectoring gives the fighter a huge degree of maneuverability and is far superior at executing acrobatic movements at lower speeds than its non-thrust vectoring competition in the F-35 and J-20A (the J-20B is expected to add thrust vectoring capabilities). Thrust vector control allows the pilot to orient the engines of the fighter independently from the fuselage, making extremely sharp turns possible, or even flying forward while pointing the nose, and weapon systems, down at an opposing aircraft.
Even the F-22 Raptor, widely seen as the most capable air-to-air fighter on the planet, is limited in its thrust vectoring capabilities in comparison. It’s worth noting, however, that the sort of acrobatics thrust vectoring allows for scrub a great deal of the fighter’s speed, making it an approach to air combat that isn’t prized by all air forces.
The Su-57 also boasts the second-highest top speed of the class, topping out at Mach 2, just a few hundred miles per hour slower than the F-22.
Conclusion: The Su-57 may be the “worst” 5th generation fighter, but it’s still a highly capable machine
All told, the Su-57 isn’t quite as advanced, quite as capable, or quite as stealthy as the other three fighters of its generation, but that isn’t to say that it doesn’t represent an important leap in capability for the Russian military. Like the F-117 Nighthawk, America’s first foray into stealth technology, game changing advancements have to start somewhere, and as far as starts go, the Su-57 is a pretty good one.
Rather than relying on stealth, a field of technology in which the Russians may be lagging behind, Sukhoi has incorporated stealth into the design of an otherwise capable platform, producing a fighter that may not be sneakier than an F-35, but remains sneaky enough to cause some real problems for opponents, even if only on the drawing board.
To date, there are so few Su-57s in existence that any capability they offer the Russian military is superficial at best, but as production continues to spin up and the design continues to mature, Russia may yet field a positively fearsome stealth fighter. And with the U.S. leaning further into updated 4th generation (non-stealth) jets like the F-15EX, being the least stealthy 5th generation fighter is still a pretty good standing compared to the 4th-gen fighters that will remain in service for decades to come.
The Su-57 may not lead the pack in the realm of stealth fighters, but it doesn’t need to in order to pose a threat.