By Kris Osborn, President Warrior
The experimental Su-47 Russian demonstrator fighter jet was somewhat of a short-lived demonstrator, yet numerous public accounts suggest that its innovations propelled development of the country's two most advanced fighter jets, the 4th-gen “plus” Su-35 and 5th-gen “Su-57.”
The Su-47 emerged in the late 90s as a developmental project, featuring a unique “forward-swept” wing designed for advanced maneuverability. The “forward-swept” wing looks quite different, as it involves a forward slanting dual wing design which scientific research explains increases “maneuverability” because it sustains airflow over the surface of the aircraft during a ‘steeper climb.”
Su-47 Advanced Science
An interesting essay in the BBC’s “Science Focus” magazine describes the maneuverability advantages associated with “forward-swept” wings.
“Forward-swept wings make an aircraft harder to fly, but the advantages are mainly down to manoeuvrability. They maintain airflow over their surfaces at steeper climb angles than conventional planes, which means the nose can point higher without the aircraft going into a dangerous stall,” the essay says.
There is a contradictory if not somewhat paradoxical quality to this configuration, given that neither of the two advanced aircraft it is credited with influencing have a similar configuration. Both the Su-35 and the Su-57 have standard fighter-jet backward-slanting wings, a circumstance which raises questions about what lessons may have been learned by the Su-47. Some of the details likely involve advanced aerodynamic concepts and next-generation engineering, yet the lessons learned are credited with improving the performance of Russia’s two most advanced aircraft.
The Su-47 was able to reach advanced speeds of Mach 2.2, yet retain high-agility at subsonic speeds, according to the BBC Science article. This enabled the aircraft to adjust its angle of attack while maintaining supersonic speed and air-combat maneuverability.
Thrust to Weight Ratio
The specific manner in which the Su-47 test aircraft influenced subsequent Russian 4th and 5th generation aircraft may be difficult to fully discern, yet the impact appears significant due to the advanced performance characteristics of the Su-35 and Su-57. As an upgraded or next-generation derivative of the high-speed Su-27, the Su-35 is credited with an ability to rival F-22 speed and thrust-to-weight ratio.
A publication called World-Defense lists the Su-35 with the highest thrust-to-weight ratio in the world, apart from an F-22 using a round nozzle. The Su-35 is listed with a thrust to weight ratio of 1.30 and the F-22 with round nozzles is listed at 1.37, something which places the Su-35 among the very best air-supremacy dog-fighting platforms in the world.
This raises questions or at least introduces the possibility that the short-lived experimental Sukhoi Su-47, and the technologies it introduced, appear to have informed the development of the Su-35. One might interpret the Su-47 as an “agility-enhancing” bridge project influencing a new generation of fighter-jet power, in large measure because advance or high thrust-to-weight ratios vastly improve the ability of an aircraft to successfully engage in air-to-air-combat.
Yet another potential advantage may pertain to stealth attributes to a degree, because the Su-47 is credited with using some radar-absorbing materials. This is something which quite likely influenced the development of both stealthy 5th-generation aircraft and quasi-stealthy 4th-gen plus aircraft such as the Su-35.
Kris Osborn is Editor of Warrior Maven – Center for Military Modernization. Osborn previously served at the Pentagon as a highly qualified expert in the Office of the Assistant Secretary of the Army—Acquisition, Logistics & Technology. Osborn has also worked as an anchor and on-air military specialist at national TV networks. He has appeared as a guest military expert on Fox News, MSNBC, The Military Channel, and The History Channel. He also has a Masters Degree in Comparative Literature from Columbia University.