RD-810
The RD-810 (РД-810) is a Ukrainian liquid propellant rocket engine burning LOX and Kerosene (RG-1) in a staged combustion cycle.[4] It has a single combustion chamber that provides thrust vector control by gimbaling of the nozzle in two axis by +/- 8°. It is being designed in Ukraine by Yuzhnoye Design Bureau for the prospective first stage propulsion of the Mayak rocket family.[4][2]
The RD-810 as well as the RD-801 are being designed based on the work of the RD-8 vernier and the maintenance and improvement of the RD-120 engines. The RD-810 can be used stand alone on a Mayak or could be used in a module of four called RD-810M to replace the RD-170 on the Zenit.[2]