Article Summary and Key Points: The Su-47, Russia’s ambitious forward-swept wing (FSW) experimental aircraft, emerged from internal politics and engineering experimentation rather than practical combat requirements.
Key Point #1 – Developed by the Sukhoi Design Bureau under controversial leader Mikhail Simonov, the jet aimed to showcase advanced maneuverability and structural innovation, particularly through its composite wings.
Key Point #2 – However, the design had inherent structural vulnerabilities and high replacement costs, rendering it unsuitable for production. Ultimately, the Su-47 became a technological showcase rather than a practical fighter, reflecting internal rivalries within Russia’s aerospace sector rather than fulfilling strategic military needs. Only one prototype was built, symbolizing a costly lesson in ambition.
Su-47: Russia’s Radical Forward-Swept Wing Fighter That Never Took Off
Over the past several decades, Russian aircraft production history has produced several examples of “one-off” aircraft. The Russian Air Force built these designs to be flown, tested, and validated for specific aerodynamic concepts. In the years before and even for some time after the Second World War, building a flying machine to wring out a design concept was understandable.
One reason was that although wind tunnels and test stands existed, the instrumentation technology was in its infancy—or even non-existent. Another was the computerized design tools used today, like the famous CATIA software, which were decades in the future.
The Su-47 forward-swept wing (FSW) demonstrator was one of those one-off designs, but it first flew in 1997. This was long after many test and design technologies became available and were widely used—even in the Russian industry.
The X-29, also an FSW configuration, inspired the aircraft’s development. It had flown for over a decade before the Su-47 was developed. The X-29 was built by the United States Air Force, NASA, and Germany’s DASA.
Even with the Iron Curtain between these countries, the concept of an aircraft with this unusual wing design was no mystery to the aerospace world. Additionally, the X-29 was a commercial failure.
So, why was the Su-47 designed in the first place?
Industrial Politics
In the 1980s, the Sukhoi Design Bureau acquired a new General Designer in the form of Mikhail Simonov. He had been in the aircraft design business all his life. But due to a stint, he had performed at the then-Soviet Ministry of Aircraft Production, his coming from an outside bureaucratic institution to ascend to the top job at Sukhoi was resented by others who had spent all their lives in the bureau.
Russia’s aerospace sector is known for its intrigue and backbiting. At this time, the Sukhoi organization was no exception. Simonov was treated as someone who had inherited aircraft designs like the Su-27 that were selling so well in the export market and had little to nothing to do with its development.
To beat back the narrative that “Simonov was no aircraft designer,” he ordered the development of the “S” series of FSW designs, the two most notable of which were the S-32 and S-37—the “S” standing for Simonov rather than the “Su-” prefix for Sukhoi.
The aircraft were the products of his preference for what was known as “super maneuverability.” In his words, the airframes were a “logical progression from the thrust-vector-equipped Su-27M prototype aircraft in exploring post-stall maneuverability.”
The Su-47
Sukhoi received no funding from the Russian Air Force (VVS) for the program, which he described as “experimental aircraft only,” which signaled that the armed forces viewed the program as lacking practical applications in combat.
Exotic materials were used to construct the Su-47, specifically the wings, which was an example of the experimental nature of these aircraft. They were made of composites that were literally laid up by hand, and their forward-swept configuration resulted in very high wing loading numbers. Any damage the aircraft would suffer in combat could cause the wing to sheer off completely.
Structural design and composites engineers looking at the design point to the fact that it would still have to be replaced if the wing did not separate from the aircraft. In 1991, the price to replace the wing would have been 6 million roubles per wing, or more than US $1.2 million under the exchange rates at the time of its design.
One of the interesting aspects of the Su-47 design was that it abandoned the separated engine arrangement that has been typical of all the Su-27 and Su-30-series designs and even the Su-57 today. Instead, the aircraft has two engines fitted to the centreline, like the F-15.
The powerplant was a nontraditional choice because the design team eschewed the usual Lyulka/Saturn AL-31F engine derivatives and instead selected the same Perm/Soloviev D-30F6 that powers the Mikoyan MiG-31.
“This engine was likely selected because it had the highest dry thrust of any Russian engine available at the time,” said one of the designers from the Perm production facility. It was also the best choice for the aircraft’s fuel efficiency requirement.
Image: Creative Commons.
Ultimately, the reasons the Su-47 was built and the single prototype flown were not realized. Demonstrating that he could oversee the design of a new aircraft and see it to completion and flight test allowed Simonov to maintain his position as the head of the design bureau.
Instead, he ended up being shunted aside to a secondary position in favor of Mikhail Pogosian, who ran Sukhoi until 2011, when he was appointed the CEO of United Aircraft-Building Corporation (OAK). “Egos,” said one Russian aerospace official when the aircraft first flew. “Sometimes they cost a lot of money.”
Su-47. Artist Rendition. Image Credit: Creative Commons.
About the Author: Reuben F. Johnson
Reuben F. Johnson is a survivor of the February 2022 Russian invasion of Ukraine and is now 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.
