Miranda (engine)

The Miranda engine is a liquid-fueled rocket engine currently being developed by Firefly Aerospace. The engine is designed to power both Firefly's MLV (Medium Launch Vehicle) and the Antares 330 from Northrop Grumman.

The Miranda engine generates a thrust of 230,000 lbf fueled by liquid oxygen (LOX) and kerosene (RP-1).

Its development was necessitated by Russia's invasion of Ukraine, the RD-181 engine previously used on the Antares was built in Russia and subject to sanctions.

Development began in 2022 and in 2024 Firefly reported substantial progress on testing the engine.