section_path: Engines/Miranda
section_name: Miranda
paragraph_text: Miranda
  
  Miranda is a liquid-fueled rocket engine currently being developed to power the company’s MLV (Medium Launch Vehicle). The Miranda will also be used on the Antares 330 rocket developed by Northrop Grumman.
  
  The Antares previously used a Ukrainian-built first stage with the Russian-built RD-181 engine and production ceased after the Russian invasion of Ukraine. Firefly will also assemble the entire first stage for the Antares 330.
  
  Like Firefly's previous engines, the Miranda will use RP-1 and LOX in a combustion tap-off cycle. It is expected to produce 1,023 kilonewtons (230,000 lb) of thrust and a specific impulse of 305 seconds (2.99 km/s) in vacuum.
  
  Development began in 2022, and in 2024 Firefly reported substantial progress on testing the engine, with 20 test fires completed. As of June 2024, the Miranda engine had entered production. To support production of the Miranda engine, the MLV and the first-stage for the Antares 300, Firefly expanded its Briggs, Texas facility from 92,000 to 207,000 square feet (8,500 to 19,200 m 2).
  
  Firefly said that it has designed the Miranda from its inception for reusability. The company plans to restart the engine multiple times as the rocket performs a return-to-launch-site maneuver for a propulsive landing.