T-50 / Project 701 / PAK FA [Perspektivnyi Aviatsionnyi Kompleks Frontovoi Aviatsyi]
Russia’s T-50 (PAK FA) fifth-generation fighter jet has received the serial index of Su-57, Aerospace Force Commander-in-Chief Colonel General Viktor Bondarev said in an interview with the website of Zvezda TV Channel on 11 August 2017. “The decision has been taken, the plane has been christened. Su-57 is what we are going to call it now". The nomenclature follows the Su-27 Flanker , Su-37 "Super Flanker", Su-47 "Berkut" designation sequence.
It was reported that the T-50 with the advanced (main) engine would perform its debut flight in the fourth quarter of 2017. Currently, the so-called first stage engine 117S is mounted on the Russian fighter. The new engine had not initally received its name and was conventionally designated as the second stage engine. The ninth prototype of the T-50 has been equipped with the Izdelie-30, fifth-generation engine, which will be tested at the end of 2017. Compared to the Izdelie-117, the engine is a new development and has already been installed in the latest Su-57. The Izdelie-117 is a modernized version of the AI-31 engine - the “heart" of the original Su-27. The new engine will enable the Su-57 to maintain cruising speed during supersonic flight, meaning the jet will be able to fly consistently at 2,000 km/h (1,200 mph).
It won’t be until 2019 that Russia’s Air Force will be beefed up with Su-57s fully loaded with the new technology, including the Izdelie-30. The engine will need to be put through a long string of tests and will be mounted on the Su-57 aircraft no earlier than 2019 or 2020. Unlike previous prototypes, the ninth prototype of the Su-57 is equipped with the full set of radio-electronic equipment that will be installed on the completed version of the jet. This will allow the aircraft to evade modern air defense systems.
The maiden flight of the T-50 / Project 701 / PAK FA, the first Russian fifth-generation fighter jet was completed successfully on Friday morning, 29 January 2010 at Komsomol'sk-na-Amur. This event was significant for several reasons.
The PAK FA is generally similar in appearance to the American F-22, though there are so many differences in detail that it is clearly an original design rather than a knock-off copy. A direct comparison with the F-22 is probably not meaningful on an unclassified basis, but Russian marketers will probably sell it as roughly equivalent in combat potential. While the F-35 is also a fifth generation stealth fighter, the low observable characteristics of this attack aircraft are said to be markedly inferior to the all-around stealth of the F-22 air supremacy fighter.
As of January 2010 a total production run of at least 150-200 aircraft for the Russian Air Force and 200 aircraft for the Indian Air Force was envisioned. If these production objectives are met, the United States might wind up with the world's third largest fleet of stealth fighters, after India and Russia.
In June 2001, India was offered 'joint development and production' of this new 5th generation fighter by Russia. Russia had been trying to sell this concept both to China and India for some time. It seems probable that China declined to participate in this project given a belief that Russia stood to gain more from Chinese participation than did China. That is, it would seem that China had determined that it could produce a superior product without Russian help. With the first flight of the Russian stealth fighter in 2010, an arguably superior Chinese steath fighter might be expected to take to the skies not too long thereafter.
The prospect that a country like Iran might buy even a few dozen PAK FA aircraft from Russia may well awaken interest in the F-22 in Israel, if not Saudi Arabia. The emergence of a Chinese counterpart stealth fighter may also re-awaken Japanese interest in the F-22. Production of large numbers of PAK FA by India would place Pakistan in a rather difficult position, unless it purchased similar numbers of stealth fighters from China.
The first stealth fighter, the American F-117A, was designed in the 1970s using a novel mathematical theory for determining radar cross-sections of general three-dimensional bodies, and optimizing it subject to constraints. Ben Rich, chief of Lockheed's Advanced Development Projects division (the so-called `Skunk Works'), wrote that "the Rosetta Stone breakthrough for stealth [fighter] technology" was a new theory developed by Pyotr Ya. Ufimtsev, not a new development in engineering. Although the theory was conceived at the height of cold war tensions in the mid-1970's, it was instigated by a research paper published by this Soviet radar engineer.
Ufimtsev is known for his works in the theory of diffraction and propagation of electromagnetic and acoustic waves. Among his fundamental contributions were the the Physical Theory of Diffraction (PTD), and the discovery of new physical phenomena related to surface waves in absorbing layers. PTD is used worldwide in the design of microwave antennas and in calculations of radar cross-section of scattering objects. In particular, this theory was used in the design of American stealth aircraft nearly invisible to radar.
CIA Director William Casey, in a briefing to the Senate Armed Services Cimmittee in January 1986 stated, "We know that the Soviets are working to acquire the technology to develop aircraft and cruise missiles employing stealth features". Secretary of Defense Caspar Weinberger stated in Soviet Military Power 1987 that "evidence suggests the Soviets have made progress in developing aircraft that may have a low observable radar signature". The US Air Force started to address the needs of future fire control systems to handle the impact of Soviet stealth aircraft. In particular, contracts awarded by the US Air Force in August 1987 were to contain risk assessments addressing technology projection and Soviet airframe observability.
In early 2002 Sukhoi was chosen as prime contractor for the planned Russian fifth-generation fighter is called the PAK FA [ Perspektivnyi Aviatsionnyi Kompleks Frontovoi Aviatsyi - Future Air Complex for Tactical Air Forces]. This intermediate class twin-engined fighter was to be larger than a MiG-29 and smaller than a Su-27. The new fighter was said to be intended to be about the same size as the US F-35 JSF, with a primary air superiority mission and ground attack and reconnaissance being secondary missions.
The aircraft was to feature a long combat radius, supersonic cruise speed, low radar cross section, super-maneuverability, and the ability to make short takeoffs and landings. In accordance with the technical requirements, the PAK FA was to have a normal takeoff weight of 20 tons, which is close to the average normal takeoff weight of the two American airplanes, the F-35 JSF (17.2 tons) and the F-22 (24 tons). The new fighter (a medium version) was to have a traditional wing form, though the experience gathered as a result of Berkut's test flights will be taken in consideration when designing the fighter. It was supposed that it was to be created using the Stealth technology, and equipped with two AL-41F engines by the Saturn scientific and industrial enterprise, a radar system with an active phased array to be produced by the Fazatron-NIIR corporation, and high-precision weapons.
In addition, the T-50 is said to have quite advanced electronic devices equipped with active phased array radar system (AESA), which can scan hundreds of nautical miles all air and ground objects, and can simultaneously target and track multiple air targets. Installed in dozens of different parts of the body can not only monitor the environment sensor, the ground also can exchange real-time data. Its "electronic pilot" analysis system continue to make scenario analysis, to provide action plans to receive a large number of missions and combat all forms of data to help pilots relieve stress, simplify the operation process, it focused on the implementation of tactics.
The T-50 takeoff and landing distance is shortened, only about 330 meters to complete the landing runway, their weapons can all be mounted inside the fuselage bomb bay to meet stealth requirements. Reportedly, T-50 can carry eight R-77 air to air missiles.
Russia's "Beyond The Headlines" website reported 07 July 2013 that Russia announced at the Paris Air Show that it had completed the fifth-generation fighter T-50 engine development work [an optimistic report]. The Russian military said they had completed the first phase of T-50 flight tests, the results showed that the Russian T-50 and US F-22 fighter can Raptor comparable to or even in certain aspects even better than the F-22. Russia's United Aircraft Corporation President Mikhail Mikhail Pogosyan said five T-50 fighter aircraft were being tested, which will enable designers to accelerate the development of Russia's process of narrowing the gap between Russia and the US.
In February 2017 it was reported that the 5th-generation T-50 (PAK FA) jet fighters will be delivered to the Russian Air Force after 2018, according to Russian Deputy Defense Minister Yuri Borisov. "Most likely this will be part of the next State Armament Program for the 2018-2025," said Borisov, adding that the fighter still needs to be perfected and the military will not rush to buy the new expensive planes. For now their functions will be performed by the 4++ generation Su-35S fighters. "We bought a small number of the T-50s, and we’re watching how they perform in tests," said Borisov. "We’re looking for defects and will make the necessary improvements so that it will eventually be the best fighter plane possible."
There is still a range of problems. In the first several years after their acquisition by the Air Force, the T-50s will have to be modernized, Pavel Bulat, director of the Mechanics and Energy Systems international Laboratory at the University of Information Technologies, said 06 February 2017. "The 5th-generation engines still do not exist, and the PAK FA still flies on modified engines from the Su-27, Su-30 and other aircraft from that series," said Bulat.
The new engine under development will help the T-50 accelerate to supersonic speed and maintain that speed during flight. "I think it will have speeds of 1.6 Mach, (about 1,200 miles per hour), depending on the location over which the flight takes place," added Bulat. "The engine will also improve the PAK FA's stealth capacity thanks to new composite materials." The new jet fighter engine will be tested within the next 18 months, and it will most likely be ready for service in 2020. "In addition to the engine, two other things must be done – perfecting the radar systems, and removing the last defects in the concept of the airframe, which makes it the most modern plane in the world today," said Bulat.
India joined the T-50 development and allocated nearly $25 billion, which indicates the T-50 project promising to meet the highest standards requirements. India is likely in 2018, with a T-50 India-specific version. Russian experts said, T-50 will also be for export, but, the Russian T-50 will create special models. Russian Air Force hoped to receive as soon as possible in 2013 the first production T-50 fighter aircraft, and planned to buy at least 10 of the fighter.
Carlo Kopp and Peter Goon wrote in 2010 that "... a mature production PAK-FA design has the potential to compete with the F-22A Raptor in VLO performance from key aspects, and will outperform the F-22A Raptor aerodynamically and kinematically. Therefore, from a technological strategy perspective, the PAK-FA renders all legacy US fighter aircraft, and the F-35 Lightning II Joint Strike Fighter, strategically irrelevant and non-viable after the PAK-FA achieves IOC in 2015. Detailed strategic analysis indicates that the only viable strategic survival strategy now remaining for the United States is to terminate the Joint Strike Fighter program immediately, redirect freed funding to further develop the F-22 Raptor, and employ variants of the F-22 aircraft as the primary fighter aircraft for all United States and Allied TACAIR needs."