Key Points – The Su-57E, Russia’s export variant of its Su-57 “Felon” stealth fighter offered to India, differs significantly from the domestic Russian version through deep customization aimed at New Delhi’s “Make in India” policy.
-The most crucial difference is Russia’s unprecedented offer of full access to the aircraft’s source code, allowing India to integrate its own domestic avionics, such as a main mission computer, and weapon systems like the Astra and Rudram missiles.
Russia’s Su-57 Stealth Fighter. Image Credit: Creative Commons.
Su-57. Image Credit: Creative Commons.
-The Su-57E also features an advanced AESA radar with GaN technology, though its performance may be subject to Russian export restrictions. This tailored approach contrasts sharply with typical Western export models.
Su-57 Fighter Variants: What are the Differences?
On June 4, Russia’s United Aircraft Corporation (OAK) raised the ante in the Indian fighter aircraft competition by making an offer to sell the next-generation aircraft to the Indian Air Force (IAF). This entry, however, is not the first time that Russia has made an effort to make India a major customer of this program.
Previously, in 2016, the program was known as the T-50 or PAK-FA, an acronym for its Russian program and prototype development phase. At the time, India had entered into the first stage of cooperation with Russia on this aircraft, with the version for India to be called the Future Generation Fighter Aircraft (FGFA) by the Indian Air Force (IAF).
New Delhi later withdrew from the cooperative agreement after the IAF had complained for two years about differences with Russia on several program details. These included cost-sharing plans, technology transfers, and the aircraft’s other technological shortcomings from India’s perspective. The aircraft India wanted would have been an almost entirely different version and would also have been a two-seat platform rather than a single-seat fighter.
So, almost a decade later, Russia is back offering India a similar—but not the same—aircraft that shares the same shape and basic performance as the Sukhoi Su-57. But it is instead called “Su-57E”.
What is it about that jet that would make India reconsider this program after previously rejecting it? How does the “E” model differ from the baseline Su-57?
Potential Su-57E Customers
The “E” suffix in the Su-57E designator literally means “export,” but there is the reality that there are a limited number of countries that Moscow would offer this fighter to for sale.
That means that the Su-57E does not have to be designed and configured like a United States export F-16—an aircraft that could be “all things to all people.”
Instead, it can be tailored to be sold to and built by a partner nation, with India being the most likely customer to fit the bill. In addition to India, discussions have been held about selling the aircraft to Algeria and possibly Iran.
However, India is probably the only nation that has the industrial capacity on a scale that could both support this aircraft and potentially engage in a license-production agreement. India has already produced close to 300 Su-30MKIs at its aircraft assembly plant in Nashik, and these Indian-built aircraft contain progressively more locally made content.
The only potential candidate with a comparable level of industrial capacity would be the People’s Republic of China (PRC). However, Beijing has shown no interest in the Su-57E aircraft and is instead focusing on the production of its own indigenously developed next-generation fighters.
The Su-57E, as offered to India, would be procured using a very similar template. The aircraft would be modified and built in India, following this model for cooperation.
How is the Su-57E Different?
Noticeable differences in the Su-57E as developed for India and the baseline model produced for the Russian Aerospace Forces (VKS) are significant, with the major points being:
– Russia, in its latest offer to India for the Su-57E, has agreed to give India full access to the source code of the software modules that are used in the aircraft. This will give India the ability to integrate any weapons it wants onto the airframe. Su-57Es are, therefore, likely to be carrying a considerable number of non-Russian weapons.
One report on the Su-57E points out that “Indian officials note this [source code] latitude eclipses anything previously granted by Western suppliers. The offer collides head-on with Washington’s rival F-35A [for India] pitch, sharpening Indo-Pacific rivalry.”
– Indian-made avionics and other onboard systems will replace Russia-made hardware in the Su-57E. This would include an Indian Main Mission Computer (MMC) and other hardware that would again mirror the type and number of India-produced components that are installed in the Su-30MKI. The use of so many Indian-made systems is important politically so that Moscow is compliant with New Delhi’s mandated “Make-in-India” requirement in its weapon systems procurement processes.
– The Su-57E features low observability modifications to the surface of the aircraft, supercruise capacity, plus advanced sensor fusion. The version being proposed to India also includes an Active Electronically-Scanning Array (AESA) radar based on Gallium Nitride (GaN) Transmit and Receive Modules (TRMs). The TRMs may be software-limited in their terms of range and the variety of modes, as they must comply with Russian export restrictions.
Su-57 Felon Fighter. Image Credit: Creative Commons.
– The Su-57E would also employ Indian-designed munitions such as the Astra Mk1 and Mk2 beyond-visual-range (BVR) air-to-air missiles, the Rudram anti-radiation missile, and an indigenously-produced precision-guided air-to-ground weapons. India’s goal here is to reduce its dependency on foreign-supplied weaponry.
One of the rationales behind the Su-57E appears to be that the use of foreign-made onboard systems and weapons in the export version provides some relief for the Russian industry. OAK has its own troubles building enough of the aircraft to meet Moscow’s own requirements.
Using an export customer to build a significant number of onboard systems enables Russia to sell the aircraft abroad in quantities that its own industry would not be capable of achieving on its own.
About the Author:
Reuben F. Johnson is a survivor of the February 2022 Russian invasion of Ukraine and is an Expert on Foreign Military Affairs with the Fundacja im. Kazimierza Pułaskiego in Warsaw. He has been a consultant to the Pentagon, several NATO governments and the Australian government in the fields of defense technology and weapon systems design. Over the past 30 years he has resided in and reported from Russia, Ukraine, Poland, Brazil, the People’s Republic of China and Australia.
