Russia Researching Future Interceptor Technologies, New Light Fighters

Piotr Butowski

On Jan. 22, Russian state development agency Rostec Corp. published a story on its website about the MiG-31 Foxhound interceptor in which it mentioned that the aircraft's successor, PAK DP or MiG-41, is currently under development. A few days later, the designation MiG-41 was removed from the text.

The program for PAK DP, an acronym that roughly translates to Future Air Complex of Long-Range Interception, deserves close attention, as the conceptual work on it has been commissioned and is financed by the Russian defense ministry. The sums allocated to this program so far are small. The PAK DP is a research project, which aims to develop an initial concept of the aircraft and formulate requirements for a subsequent development effort.

Available documents show that the main contractor for the PAK DP research work is the United Aircraft Corp. (UAC), which on Dec. 25, 2018, secured a contract from Russia's defense ministry. In May 2019, UAC ordered Russian Aircraft Corp. (RSK MiG) and Sukhoi to develop the aircraft concept. It is not clear whether each company is developing its own concept or if Sukhoi has a section of work under the RSK MiG project. That Sukhoi received the order directly from UAC, and not through RSK MiG, suggests the former.

RSK MiG and Sukhoi have commissioned individual parts of the work to subcontractors. In 2020, RSK MiG ordered airborne missile designer and manufacturer GosMKB Vympel to conceptualize arming the PAK DP with air-to-air missiles. At the request of RSK MiG, part of the research work carried out in 2020—though it is not known what work specifically—was undertaken by the Moscow Institute of Thermal Technology (MITT). The engineering school deals with intercontinental and tactical ballistic missiles, as well as hypersonic technologies.

Even before the contract from the defense ministry, RSK MiG had requested the Central Aerohydrodynamic Institute (TsAGI) perform tests of the PAK DP model in the T-102 wind tunnel in 2017 and 2018. The T-102 is a low-speed tunnel; the research concerned the characteristics of the PAK DP in various configurations of the wing high-lift devices at speed Mach 0.2 and at angles of attack from -7 deg. to 36 deg. A total of 246 measurements of the model were made.

Judging by the meager value of these contracts so far—2.5 million rubles ($33,000) for Vympel, 3 million rubles for MITT and 8.9 million rubles.for TsAGI, the project remains in its early stages.

In 2019, as part of the PAK DP program, Sukhoi commissioned the development of instructions for counteracting foreign intelligence. With the launch of any military equipment development program in Russia, an accompanying document is developed in which it is determined what features of the new design must be hidden, as well as ways to hide them—including disinformation.

The PAK DP program was broadly referenced by representatives of the Russian aviation industry and the air force in previous years.

In August 2017, Ilya Tarasenko, then the director general of RSK MiG, said that PAK DP will implement all the technologies that the company has to offer. In November of that year, Sergey Korotkov, UAC vice president and general designer, said that PAK DP will fight against hypersonic targets. “We will have to deal with hypersonic carriers and their weapons, which are also hypersonic,” Korotkov said.

People involved in the PAK DP project have publicly used the designation MiG-41 several times. In the above-mentioned RSK MiG order for PAK DP's wind-tunnel tests, the airplane is called “izdeliye,” or “product” 41.

The PAK DP project dates back to the days of the Soviet Union. In the 1980s, MiG was designing MDP, a multifunction long-range interceptor that was developed to achieve a range of 7,000 km (4,350 mi.) while flying at a cruising speed of Mach 2.35.

Summing up the available information, it can be said that the purpose of the PAK DP is to fight the most demanding air targets, including hypersonic ones as well as low-orbit spacecraft. The aircraft would also fight against threats similar to those targeted by the current MiG-31, such as heavy bombers and strategic cruise missiles. PAK DP is to achieve the same cruising speed as the MiG-31 at 20 km altitude, Mach 2.35, but with a much longer radius of action.

When speaking about the timing of the PAK DP program, UAC President Yury Slyusar said in August 2018 that the creation of the new interceptor “has to be synchronized with exhaustion of the MiG-31's lifetime.” In other words, the 2030s, Slyusar added.

For Russia, however, the date is so distant that it is difficult to forecast anything. Current trends in the Russian economy and the aviation industry indicate that Russia will not be able to afford such an aircraft. It is possible that the tasks currently planned for PAK DP will be partially moved to an intercepting variant of the Su-57 fighter, especially after arming it with the new very-long-range missile “izdeliye 810.” In addition, the Russians may again extend the service life and upgrade the current MiG-31 fleet in order to keep it in service well beyond 2030.

Light Strike Aircraft, With or Without Pilot

RSK MiG, and Sukhoi too undoubtedly, are conducting conceptual work on variants of lightweight tactical combat aircraft. They all have a lower status than the PAK DP project, given there is no procurement or government financing for the variants under study.

Sergey Chemezov, the CEO of Rostec, to which UAC, RSK MiG and Sukhoi belong, told reporters in early December 2020 that the corporation is developing the concept of a fifth-generation fighter “in the light- and medium-weight class.”

“This could be a universal platform in manned and unmanned versions,” he added. On Dec. 16, 2020, Andrei Yelchaninov, deputy chairman of the Military-Industrial Commission board, told the Izvestia newspaper that “MiG is working on the creation of a light strike aircraft, which can be either manned or unmanned.”

Both Chemezov and Yelchaninov underlined that the work “is conducted on an initiative basis and is not funded by the state.” They also emphasized the export orientation of this project and possible cooperation with a foreign partner.

One of Russia's possible partners is the United Arab Emirates (UAE). In February 2017, during the IDEX 2017 exhibition, Chemezov announced that Russia and the UAE had agreed to jointly create a new-generation lightweight fighter. Chemezov proclaimed the signing of an appropriate contract later that year.

The aircraft would be produced in the UAE and was intended for the UAE Air Force and neighbor services. In the following years, apart from a few general declarations that the project is up to date, details were not available.

There are three known acronyms for Russia's new lightweight fighter project.

The official strategy of UAC for 2016-2035 was published in December 2016. That document interchangeably uses “LFI,” an acronym translated as Lightweight Tactical Fighter, or “PLIB,” translated as the Future Lightweight Fighter-Bomber, as the names of this program.

In 2018, the United Engine Corp. (UEC) said in a presentation that the LFI/PLIB's powerplant could be a single “izdeliye 30” turbofan developed for the Su-57 fighter. According to the same presentation, two modified “izdeliye 30” engines would be used to provide propulsion for the PAK DP.

The RSK MiG uses the acronym “LMFS” for its lightweight fighter project. In December 2019, RSK MiG ordered TsAGI to “calculate the aerodynamics of a lightweight multifunction tactical aircraft (LMFS) in a twin-engine configuration” and compare it with foreign counterparts. One of the known RSK MiG LMFS designs is a canard that has a large delta wing, with small control surfaces at the rear and on the sides of the engine nacelles. It has a maximum takeoff weight of 24,500 kg (54,000 lb.) and is designed to reach speeds of up to Mach 2. The ferry range with additional fuel tanks will be 2,160 nm, and the basic weapon load is to be carried inside the fuselage.

The current conceptual work on the RSK MiG LFMS is a continuation of the LFI lightweight tactical fighter program launched by MiG as early as 1986. The LFI fighter was later refreshed in the form of the E-721 project for the purposes of the PAK FA stealth fighter program. In 2002, the MiG E-721 lost the PAK FA competition for the Sukhoi T-50 project, the present Su-57.

https://aviationweek.com/defense-space/budget-policy-operations/russia-researching-future-interceptor-technologies-new-light