Russia's is due to unveil its first stealth fighter at an air show outside Moscow.
The Sukhoi T-50, which is being developed jointly by Russia and India, made its maiden flight at a Far East air base in January 2010, but is being presented to the public at Moscow's International Aviation and Space Show outside Moscow for the first time today.
Russian officials have said the final version of the two-engine single-seater fighter will not be ready until the end of 2016.
Two prototypes are expected to fly over Zhukovsky air field outside Moscow.
The jet closely resembles the U.S. F-22 Raptor, which first flew about two decades ago and entered into service in 2005.
compiled from agency reports