Technical problems forced Russia to abort a flight of its T-50 stealth plane at an air show outside Moscow on Sunday, officials said.
The Russian air force "stopped the flight due to technical defects," a spokeswoman for the MAKS international airshow told AFP.
The fighter was still undergoing tests so technical glitches were to be expected and the pilot "simply chose not to take risks," the spokeswoman said.
Prime Minister Vladimir Putin attended the air show on Wednesday, when the T-50 made its first public flight.
The spokeswoman said the T-50 had flown without a hitch at the air show over the previous four days.