The RD-8 engine was developed by Yuzhnoye Design Bureau for the second stage of the Zenit rocket. It has four hinged chambers and a single turbopump unit. The fuel pair is LOX/kerosene. Vacuum thrust is 78.5 kN and its specific impulse in vacuum is 342 s.
The engine was designed for long service life (up to 4000 seconds), high reliability, and is the first smaller upper stage engine to use the staged combustion cycle.