Video of X-29 and Su-47

High AoA maneuver of X-29

Flight Demonstration of Su-47

Two experimental aircraft, X-29 and Su-47, for forward swept wing developed by US and Soviet respectively. Both adopted composite structure to mitigate inherited aero-elastic problem in forward swept wing; if wing-tips of forward swept wing is disturbed by high AoA stream, LE of tip twists further and fall in divergence status. Uni-directional composite structure forces twist direction of the wing artificially although it costs more than conventional wing. 

Forward swept wing could show better performance potential in transonic region via aileron control, high AoA maneuverability, and lift distribution. Indeed, US and Russia attempt to build these experimental aircraft to test their potential. However, TVC is more effective way to achieve high AoA which do not cause heavy modification of OML and structure of the aircraft. Careful build of composite structure is also another obstacle of practical use of forward swept wing. So, now main-stream of the jet fighter is still backward swept wing.  

Adoption of composite structures on X-29's wing

<http://aerospaceengineeringblog.com/aeroelasticity-composites-and-the-grumman-x-29/>

Adoption of composite structures on X-29's wing - 2

Most recent forward swept wing jet from Russia's SRT-10 trainer