Russia’s Sukhoi T-50 PAK-FA fifth-generation stealth fighter is slated to enter service with the Aerospace Forces in 2019. It has been given designation Su-57. The plane is a 5th generation multi-role, single seat, twin-engine air superiority/deep air support fighter. Currently, nine Su-57 prototypes are conducting flight trials and undergoing technical testing with two additional aircraft to be handed over to the Russian Aerospace Forces for trials by the end of the year. Two Su-57 planes simulated an air combat at the MAKS-2017 international airshow on July 19.
Russian Sukhoi T-50 fighter jets perform amazing stunts at MAKS 2017
The fighter will complete its first set of flight tests by the end of 2017, said the commander-in-chief of the Russian Aerospace Forces, Viktor Bondarev. According to him, «We do have something to be proud of. The first phase of PAK-FA trials will be over in December and eventually we will receive such planes».
Various hardware elements designed for a future 6th generation fighter jet have been tested on the Su-57 during flight tests.
The new plane is designed to rival the American F-22. It offers much of the same capabilities as the new fifth-generation fighter, with exception of stealth. The Su-57 possesses advanced avionics such as active phased array radar and sensor fusion. The radar offers both forward-looking and side-scanning capabilities.
Combined with a high fuel load, the Su-57 has a supersonic range of over 1,500 km, more than twice that of the Su-27. Maximum speed: at altitude: Mach 2 (2,140 km/h; 1,320 mph), supercruise: Mach 1.6 (1,700 km/h; 1,060 mph). Range: 3,500 km (2,175 mi; 1,890 nmi) subsonic, 1,500 km (930 mi; 810 nmi) supersonic. Service ceiling: 20,000 m (65,000 ft). Operational endurance: up to 5.8 hours. Maximum take-off weight: 35480 kg, maximum operational load: 10 tons. During testing the aircraft demonstrated the ability to achieve a 384 meters per second climbing rate. It could equal to the peak of Mount Everest, the highest mountain on Earth, in a mere 23 seconds.
The fighter is armed with a 30 mm autocannon. T-50 carries four long-range missiles in its two main weapons bays and two short-range missiles in the wing root weapons bays. The primary medium-range missile is the active radar-homing K-77M, an upgraded R-77 variant with AESA seeker and conventional rear fins. The short-range missile is the infrared-homing ("heat seeking") K-74M2. The armament can include further developed and modified variants of Kh-35UE (AS-20 «Kayak») anti-ship missile and Kh-58UShK (AS-11 «Kilter») anti-radiation missile.
The main bays can also accommodate air-to-ground missiles such as the Kh-38M, as well as multiple 250 kg KAB-250, or 500 kg KAB-500 precision guided bombs.
For missions that do not require stealth, the T-50 can carry weapons on its six external hardpoints. PAK-FA chief designer Alexander Davydenko has said the installation of BrahMos supersonic cruise missile on the Su-57 is an option. Only one or two such missiles may be carried due to heavy weight of the BrahMos.
According to the plans, the aircraft will carry Р-37М (AA-13 Arrow) air-to-air missile with a maximum range of 370 km. The missile is now in production to equip upgraded Russian MiG-31BM Foxhound interceptors. It is designed to shoot down AWACS and other C4ISTAR aircraft whilst keeping the launch platform out of range of any fighters that might be protecting the target. The KS-172, an even more agile long-range air-to-air missile with a maximum range of 460 km, is at the stage of development.
The Sh-121 multifunctional integrated radio electronic system includes X band active electronically scanned array (AESA) radar, or active phased array radar. The use of the L-band in the operation of the radar in the air-to-air mode is the main means of detecting low-profile aircraft from the T-50.The avionics suite comprises the 101KS Atoll electro-optical system which allows to control airspace in the optical range around the perimeter of the aircraft, as well as to protect the aircraft from attacking missiles. Four sensors provide for infrared vision to help the pilot during maneuvers at low altitude or when landing. There are systems for generating interference in the infrared range. The Atoll also features ultraviolet missile warning sensors and 101KS-N navigation and targeting pod.
Two N036L-1-01 L band transceivers on the wing's leading edge extensions handle the N036Sh Pokosnik friend-or-foe identification system and are also used for electronic warfare purposes. The T-50 will have secure communication links to share data with all other friendly aircraft in the area, as well as airborne and ground-based control points.
A new avionics suite is being developed to use indigenous Russian multi-core microprocessors and a new indigenous real-time operating system. It’s expected to make use of fiber-optic channels with a throughput of the more 8 Gbit/s, which is up from 100 Mbit/sec for traditional copper wires.
The T-50 has a glass cockpit with two 38 cm (15 in) main multifunctional LCD displays. Positioned around the cockpit are three smaller control panel displays. The cockpit has a wide-angle (30° by 22°) head-up display, and Moscow-based Geofizika-NV provides a new NSTsI-V helmet-mounted sight and display for the ZSh-10 helmet. Primary controls are the joystick and a pair of throttles. The aircraft uses a two-piece canopy, with the aft section sliding forward and locking into place. The canopy is treated with special coatings to increase the aircraft’s stealth.
The first T-50 aircraft will be powered by interim Saturn AL-41F1 afterburning turbofans producing 32,500lbs thrust each. The same engine is installed on the new Su-35 fighter. It is a highly improved and uprated variant of the AL-31 that powers the Su-27 family of aircraft. A new power plant (Product or Izdelie 30) is being developed. It has not yet received its name. The new engine is supposed to provide 17-18% more thrust, improved fuel efficiency, and higher reliability than the AL-41F1.
The plane’s body incorporates all-moving horizontal and vertical stabilizers, which toe inwards to serve as the aircraft's airbrake. The advanced flight control system and thrust vectoring nozzles make the aircraft departure resistant and highly maneuverable in both pitch and yaw. The plane is capable of performing very high angles of attack maneuvers such as Pugachev's Cobra and the Bell maneuver, along with doing flat rotations with little altitude loss.
The T-50 is not an «invisible» aircraft but it vastly uses stealth technology. It makes extensive use of composites, comprising 25% of the structural weight and almost 70% of the outer surface. The plane boasts internal weapons carriage. The payload is housed in two tandem main weapons bays between the engine nacelles and smaller bulged, triangular-section bays near the wing root. It eliminates drag from external stores and enables higher performance compared to external carriage, as well as enhancing stealth.
The airframe incorporates planform edge alignment to reduce its radar cross-section (RCS); the leading and trailing edges of the wings and control surfaces and the serrated edges of skin panels are carefully aligned at several specific angles in order to reduce the number of directions the radar waves can be reflected. The infrared search and track system is turned backwards when not in use, and its rear is treated with radar-absorbent material to reduce its radar return. Radar blockers are used in front of the engine fan to hide it from all angles.
It is believed that the T-50 is more maneuverable than its US rivals – the F-35 and F-22. The plane has a comparative advantage in air engagements. Compared to the F-22, the PAK-FA is faster, has a longer operational range, and better target detection. «It certainly has greater agility with its combination of thrust vectoring, all moving tail surfaces, and excellent aerodynamic design, than does the F-35», said former US Air Force intelligence chief Lt. General David Deptula.
India and Vietnam are already on the list of potential buyers.
Highly maneuverable, with supercruise capability and advanced avionics, the Su-57 is second to none in the world. When in service, it will put an end to the US quarter century-long monopoly on the design of very low observable (VLO) or stealth aircraft.
