Russia Guarantees India Unprecedented Control Over Su-57 Fighters with Transfer of Full Source Codes

The Russian state owned United Aircraft Corporation on June 4 announced that the license production deal for Su-57 fifth generation fighter aircraft currently being offered to India would unprecedentedly provide the Indian Defence Ministry with full access to the aircraft’s source code. Such access would ensure full autonomy not only in operating the aircraft, but also in modifying their avionics and integrating new avionics and weaponry developed both in India and by third parties. The codes of fifth generation fighters are considered particularly sensitive, as software forms a far more central part of their capabilities that was the case on older aircraft. The F-35 as a result has over 10 million lines of software code, and the Chinese J-20 and FC-31 estimated to have similarly complex code. Although the Su-57’s code is thought to be far simpler, it is still likely significantly more complex than that of the older American F-22 which uses much older computer architecture. Due to its sensitivity, the sharing of a fifth generation fighter’s full software code by Russia would be a wholly unprecedented development, and one that indicates a particularly high degree of trust in the Delhi as a strategic partner.

The Indian Defence Ministry has shown an interest in the Su-57 since the early 2010s, although major delays to the fighter program were a primary factor preventing orders from being placed. The fighter’s intensive combat testing in the Ukrainian theatre, including for air defence suppression, air to air combat, operations in heavily defended enemy airspace, and precision strike operations, has reportedly served to increase confidence in the program, as has the confirmation of the first export order by Algeria, which will begin to receive the fighters before the end of the year. The new Su-57M1 variant is also expected to become available by the end of 2026, and has a widened airframe capable of supercruising at higher speeds and benefitting from superior stealth capabilities, as well as a new primary radar and new AL-51F engines. The significant losses faced by India’s French-supplied Rafale fighters in engagements with Pakistan’s Chinese-supplied J-10C fighters in early May are considered likely to have added further urgency to plans to procure the Su-57, as have Pakistan’s plans to begin receiving its own fifth generation fighters from China by the end of 2026, which raise the possibility of Indian fighter units being left at an even steeper disadvantage.

After the Su-57 made its debut appearance in India at the Air India 2025 aerospace exhibition in February, it was confirmed that a license production deal was being considered. In the first week of March Russian Ambassador to India Denis Alipov elaborated regarding the terms on offer: “We are offering our own fifth generation fighter. We have the best machine, Sukhoi-57. We just showed it, displayed it at Aero India last month in Bangalore. It is very competitive.” “We are offering not only to sell but to co-produce. We offer technology sharing. We offer industry with creation of necessary industrial facilities for production. We are open to configuration changes. So this is a very lucrative deal that we offer to India,” he added. Russian state arms export conglomerate Rosoboronexport subsequently on March 7 revealed that license production in India could commence quickly through modernisation of the country’s existing production line for the older Su-30MKI ‘4+ generation’ fighter, which it observed “could be swiftly adapted to produce the Su-57E.”

India previously produced at least 222 Su-30MKIs under license, which upon entering service were by far the most costly non-Western fighters ever procured, and became considerably more expensive due to extensive modifications made domestically. The scale of Su-30MKI procurements sets a precedent for India to potentially become a major operator of the Su-57. In contrast to American fifth generation fighters, the Su-57 was designed to maintain similar operational costs and maintenance requirements to its fourth generation predecessors, which makes procurements on a comparable scale to the Su-30MKI potentially highly affordable.

With a number of reports indicating that Russia and India are close to finalising a deal, the United States has sought to apply pressure on Delhi to prevent it from signing major new defence contracts with Moscow. On June 4, U.S. Secretary of Commerce Howard Lutnick stressed that many of Delhi’s policies “rubbed the United States the wrong way,” adding: “For instance, you generally buy your military gear from Russia. That’s a way to kind of get under the skin of America if you’re going to buy your armaments from Russia.” His statement followed repeated threats under the first Donald Trump administration to place economic sanctions on India if it procured Russian S-400 long range air defence systems, which the Indian Defence Ministry nevertheless proceeded to order in October 2018 under a $5.2 billion contract. Lutnick’s statement also followed a statement by President Trump in February that the United States would offer the F-35 fifth generation fighter to India as part of a broader increase in arms exports to the country. “We’ll be increasing military sales to India by many billions of dollars. We’re also paving the way to ultimately provide India with the F-35 stealth fighters,” the president stated at the time. The decision to offer the F-35 was widely assessed by analysts to be motivated in large part by the perceived need to prevent India from procuring the Su-57.

Pressure from Washington to prevent a Su-57 export agreement is expected to continue to mount, both before contracts are signed, and in the aftermath to seek to press Delhi to cancel its procurement plans. This would mirror a broader trend in American efforts to pressure clients for Russian armaments across the world to instead procure Western defence equipment, which have been ongoing since the 1950s with varying degrees of intensity, but became official policy in President Trump’s first year in office with the passing of the Countering American Adversaries Through Sanctions Act. India is nevertheless considered likely to proceed to procure the Su-57, with the F-35 not considered a realistic option for political reasons. Although the provision of full source codes for the Su-57 is unprecedented, Russia has long provided very high levels of autonomy to operators of its combat aircraft, which contrasts sharply with the United States which has been by far the most restrictive. American fighters supplied to most countries outside NATO have little to no capability to be used for combat operations without approval from Washington, with restrictions on the F-35 being particularly severe due to the program’s extreme centralisation through the ALIS and ODIN systems that link all F-35s worldwide. Russia’s offer to provide full source codes has severed to further widen the already extreme contast in the levels of autonomy between it and the United States as countries seeking to supply fifth generation fighters to India.