E-2
A kerosene and liquid oxygen rocket engine using oxidizer-rich staged combustion, now offered for sale to small launch vehicle companies.
Why it matters
Staged combustion gets more performance from each kilogram of propellant but is hard to build. Offering E-2 for sale gives launch vehicle companies an option besides developing their own engine.
How the technology works
In an oxidizer-rich staged combustion cycle, part of the oxygen runs through a preburner that drives the turbopumps, then all the gas goes into the main chamber, so nothing is dumped overboard. Launcher reports a 200-second test firing.
Sources
Updated Oct 22, 2026 · How we source facts · Suggest a correction