Russia’s Su-57 fighter emerged in 2022 emerged as the most throughly combat tested aircraft from the new fifth generation, and having been deployed for combat operations in Ukraine it was assigned roles ranging from air defence suppression to long range air to air combat which were far more complex than those any other stealth fighter in the world has yet engaged in. Since the first airframe belatedly entered service in December 2020 the scale of Su-57 production has been continuously expanded, while the aircraft’s capabilities and its armaments suite have both continued to grow. As the Untied States and China pioneer the development of the world’s first sixth generation fighters, the Russian fifth generation fighter increasingly appears intended to contend at a ‘5+ generation’ level integrating a range of sixth generation technologies which are currently under development. These range from more advanced forms of artificial intelligence to a pilotless flight mode and access to drone wingmen and both electromagnetic and hypersonic weapons.
Although the Su-57’s capabilities are expected to improve significantly over the next decade, the fighter’s current armaments suite are already highly formidable with the aircraft compatible with a wider range of weapons than any other of its generation. Each Su-57 has two tandem primary weapon bays and two additional smaller bays near its wing roots, with the aircraft’s stealth capabilities necessitating internal carriage of armaments. Although the fighter can deploy additional ordinance externally, this compromises its stealth profile and as a result will be avoided for most missions to preserve survivability and reduce adversaries’ reaction time and situational awareness. With the capabilities of the armaments it has access to being a key determinant of any fighter’s combat potential, a look at all weapons currently reported to be carried in the Su-57’s internal bays is given below to provide important insight into the state of the fighter program:
Air to Air
Cannon: The Su-57’s most basic armament is the 9A1-4071K 30mm autocannon, which can fire up to 1500 rounds per minute and is embedded in the fighter’s right LEVCON root. A derivative of Soviet era guns, the cannon can engage targets close to 2km away and is intended primarily for close range air to air combat to supplement the two visual range air to air missiles carried internally by the fighter. The possibility of fighters’ main cannon being replaced by laser weapons in future has been raised repeatedly in the past.
IR Guided Air to Air Missile: The K-74M2 is the lightest missile carried by the Su-57 with two weapons bays in the fighter’s wings each housing a single one. The missile is based on the Soviet R-73, and has a reduced ceros section for internal carriage although a new clean sheet design the K-MD is currently under development to succeed it. The R-73 was the first missile in the world capable of engaging targets at high off boresight angles, initially at 60 degrees, and was found in NATO testing to provide an overwhelming advantage at close ranges. The R-74M2 improves this to 75 degrees, integrates a more reliable seeker and has a greater range. It is nevertheless considered less capable than its leading foreign competitor the Chinese PL-10 which is a clean sheet design from the mid 2010s.
Long Range Air to Air Missile: The K-77M missile was developed to revolutionise the beyond visual range air to air performance of the Su-57 and other Russian fighters, and has been named by some as the most capable weapon of its class in the world excluding oversized missiles such as the R-37. The missile has an engagement range of close to 200km and is one of very few in the world to use an AESA radar for guidance. It is optimised to target small and agile fighter sized, and uses a nose mounted active phased array antenna (APAA) guidance system, which gives it likely the longest ‘no escape range’ of any air to air missile worldwide. Russian state media outlet RT explained the K-77M’s APAA technology as follows: “An active phased array antenna consists of a large number of cone-shaped cells installed under a transparent-to-radio-waves cap on the nose of the missile. Each cell receives only a part of the signal, but once digitally processed, the information from all cells is summarised into a ‘full picture,’ enabling the K-77M missile to immediately respond to sharp turns of the target, making interception practically inevitable.”
‘AWACS Killer’ Long Range Missile: The R-37M was initially developed to equip Russian MiG-31 Foxhound interceptors, and boasts an unrivalled Mach 6 speed, 400km engagement range and very large 60kg warhead. The large size of Russian fighters such as the Su-35 and Su-30SM means they can also carry these oversized missiles, albeit only four per aircraft where Foxhounds carry six. The Su-57 uses a special derivative of the missile the izdeliye 810 which can reportedly be carried in its internal weapons bays. The missile is capable of engaging fighter sized targets, but is also optimised to neutralise support aircraft such as tankers and airborne early warning jets, as well as heavy bombers, at long ranges. The missile provides the Su-57 with the longest engagement range of any fifth generation fighter in the world.
Air to Ground
Guided Bomb: The KAB-250 bomb using GLOSNASS assisted guidance is the standard gravity weapon used by the Su-57 fighter, although with the aircraft better optimised to standoff missions the frequency with which it will be employed in a bomber role remains in question. The Su-57’s American counterpart the F-22, which notably lacks the ability to carry anything other than gravity bombs for air to ground combat, has deployed the American equivalent to the KAB-250 the GBU-39 for all its combat missions. Combined with the Su-57’s stealth, its ability to operate without a radar signature, and its laser defences designed to neutralise infrared guided missiles, the aircraft could be a formidable bomber when properly equipped.
Penetrator Bomb: The KAB-500 was designed to penetrate hardened targets and deploys a large 380kg warhead for this purpose.
Gliding Cluster Bomb: The PBK-500U Drel has among the most outstanding capabilities for a gravity bomb deployed by fighter sized aircraft, and uses both internal and satellite guidance with an inbuilt identification friend or foe system. The bomb is designed to neutralise mass armoured formations, and each weighs over 500kg. Each notably glides to its target and can engage 30-50km away with high precision and a ‘fire and forget’ capability, with a single submunitions cluster reportedly sufficient to destroy an entire missile battery or a tank column. Each bomb contains fifteen self-guided anti-tank element charges with guidance systems optimal for engaging moving targets. The usefulness of glide bombs for engaging defended targets without operating within range of their air defences was demonstrated from the spring of 2023 by Russian Air Force operations in Ukraine.
Cruise Missile: First combat tested in Syria in 2018 from Su-57 pre production models, the Kh-59MK2 was designed as the fighter’s primary air to ground armament is optimised for neutralising small hardened targets at long ranges of close to 300km. The missile uses a 320kg penetrating warhead, but can also be equipped with a smaller pellet warhead designed to affect targets over a wider area. Other warheads proposed have included a more powerful penetrator and a cluster munition carrier. The missile is subsonic which allows it to cover a greater range despite its relatively small size, but this also makes it somewhat easier to shoot down.
Light Cruise Missile: At little over half the weight of the Kh-59, the Kh-38 can be carried in greater numbers and provides an effective successor to the widely used Soviet Kh-25. The missile was designed to be carried internally by the Su-57 using folding wings, but has been combat tested in Syria by older aircraft including the Navy’s MiG-29K fighters. The missiles have much shorter ranges and smaller payloads, but are suitable for engaging less well defended and less fortified targets allowing each Su-57 to deliver more ordinance than if armed with heavier longer ranged Kh-59s.
Anti Radiation Missile: The Kh-58UShKE is a derivative of the Russian Air Force’s widely used anti radiation weapon modernised for use by the Su-57 and redesigned with folding fins to be carried in its internal weapons bays. The missile’s 250km engagement range complements the Su-57’s own very high endurance, while its Mach 3.6 speed make makes it one of the fastest in the world. The Kh-58UShKE’s range is over double that of the original Kh-58 developed in the 1980s. Since the retirement of the MiG-25BM, which was developed and combat tested as a dedicated air defence suppression platform, the Kh-58 has been deployed primarily from multirole aircraft. Anti radiation missions have taken on a renewed significance as the Russian Air Force engaged Ukraine’s massive arsenal of S-300 air defence systems from February 2022, which were supplemented by Patriot systems delivered by NATO members from the spring of 2023.
Anti Ship Cruise Missile: The Kh-35U is currently the Su-57’s primary anti ship cruise missile, and boasts a range exceeding 250km with the ability to approach targets in its terminal phase just four metres above water surface. Each carries a 250kg warhead. The missile is subsonic and relatively light and low in cost, allowing even a half squadron of fighters to carry very large numbers sufficient to overwhelm the defences of a wide range of targets. The Su-57 is expected to receive more capable but heavier anti ship weapons in future, most notably a miniaturised derivative of the Kh-47M2 hypersonic ballistic missile, which will provide a range several times as long.