The PAK FA is a fifth generation multirole fighter aircraft and the first operational stealth aircraft for the Russian Air Force. Although most information is classified, sources within in the Sukhoi and Defense Ministry have openly stated that the aircraft will be stealthy, supermaneuverable, have supercruise capability, incorporate substantial amount of composite materials, and possess advanced avionics such as active phased array radar and sensor fusion.The T-50 has a blended wing body fuselage and incorporates all-moving horizontal and vertical stabilizers; the vertical stabilizers toe inwards to serve as the aircraft's airbrake. The aircraft has adjustable leading edge vortex controllers (LEVCONs) designed to control vortices generated by the leading edge root extensions, provide trim, and improve high angle of attack behaviour, including a quick stall recovery if the thrust vectoring system fails. The T-50's two Saturn 117 engines incorporate thrust vectoring (TVC) nozzles whose rotational axes are each canted at an angle, similar to the nozzle arrangement of the Su-35S.