The RD-0109 is a rocket engine burning liquid oxygen and kerosene in a gas generator combustion cycle.

[1] After the success of Sputnik 1, Korolev sent series of letters to the Central Committee of the Communist Party of the Soviet Union proposing a bold plan to send robotic spacecraft to Mars and Venus.

[3] Korolev's OKB-1 design bureau initially competed two projects for the Block-E propulsion: 8K72, using the S.A. Kosberg's OKB-154 RD-0105, and the 8K73, using Glushko's OKB-456 RD-109 engine.

It also introduced an innovation attributed to S.A. Kosbergs in its construction, that has been a staple of Soviet (and later Russian) engines.

It used a corrugated metal construction for the cooling jackets, with the lower section of the nozzle lacking an external liner, to save weight.

[1] This new version was christened as the RD-0109 and entered service on the December 22, 1960, launch of a (Vostok) spacecraft aboard a Vostok-K 8K72K.

It was the third Vostok spacecraft and the first spaceflight to send animals into orbit and return them safely back to Earth.