Russian Fith-Generation Fighter Jet.The fighter will enter service with the armed forces in 2016,&amp; not 2015 as previously announced,President Vladimir Putin said at a live Q session with the Russian public in April.The Defense Ministry had earlier said the jet would be ready in 2015.The T-50, also known as PAK-FA (future tactical fighter aircraft), first flew in January 2010 and was presented to the public at the Moscow Air Show in 2011.