Fifth Generation?

A look at the PAK FA fighter, which took its maiden flight Jan. 29, reveals both cutting-edge technology and some compromises. The aircraft employs composite structure in the forward quarter, but its round, thrust-vectoring exhaust nozzles are not stealthy, although Sukhoi claims infrared, optical, and radar low observability. The rear-looking radar or electronic countermeasures boom between the exhausts makes it highly reminiscent of Sukhoi’s current Flanker fighters. The aircraft’s spherical infrared search-and-track ball forward of the windscreen also seems counter-stealthy. This same feature on the Lockheed Martin F-35 appears within a faceted chin aperture. Still photos suggest two sizable internal weapons bays between the engine fairings, but not readily explainable are two faceted blister fairings outboard of the engine intakes. Sukhoi claims the PAK FA will be able to supercruise and has shown prototypes of the aircraft’s active electronically-scanned array radar, like the ones on US stealth aircraft. (Also see Russian Raptor, above)