MOSCOW, December 14. /TASS/. Three Russian engines RD-181 have been handed over to the Orbital Sciences Corporation, the research and industrial association NPO Energromash said on its website on Friday.

"On December 12, three RD-181 engines were handed over to the US customer," the Orbital Sciences Corporation said in the news release.

This is a second consignment of engines delivered to the US company this year. Two RD-181 engines were handed over in June.

NPO Energomash provides RD-181 engines for the United States’ space rockets Antares, designed by Orbital Science Corporation. The main design of the launch vehicle’s first stage was developed by Ukraine’s design bureau Yuzhnoye. The manufacture of the first stage is another Ukrainian enterprise - the A.M. Makarov Machine Building Plant. The first stage is equipped with two oxygen-kerosene engines RD-181.