Firefly Aerospace conducts first hot fire of new Miranda rocket engine

Firefly Aerospace's Miranda rocket engine hot fire test (Credit Firefly Aerospace)

This week, Firefly Aerospace announced their first successful hot fire test of their Miranda rocket engine that will be the first stage of Northrop Grumman’s Antares 330 and their own Medium Lift Vehicle.

The test is a major step forward for the company as they are aiming to meet a mid-2025 launch target for the new rocket.

The MLV (and Antares 330) will utilize 7 Miranda engines on the first stage and will be capable of producing 1.6 million pounds of thrust and the ability to deliver up to 10,000 kg of payload to the International Space Station on the Antares 330.

A render of the Medium Launch Vehicle (Credit Firefly Aerospace)

The MLV will be capable of sending up to 16,000 kg low Earth orbit as it will utilize the Miranda vacuum engine whereas the Antares 330 will use a Castor 30XL solid-fueled rocket motor for its first launches before an eventual transition to the Miranda vacuum engine.

The Miranda engine uses liquid oxygen and rocket propellant-1 (RP-1), and triethylaluminium-triethylborane to ignite the engine, which produces the quick green flash seen in the photo above.  The MLV will stand 55.7 meters (183 feet) tall and will have a 5.2-meter payload fairing

CEO of Firefly Aerospace, Bill Weber, had this to say, “The incredible progress on our Miranda engines – designed, built, and tested in-house in just over a year – is another example of Firefly setting a new standard in the industry, building on the legacy of Firefly’s rapidly developed Reaver and Lightning engines, Miranda is the fastest propulsion system we’ve built and tested to date. This achievement reflects our rapid, iterative culture and our vertically integrated approach that allows us to quickly scale up the flight-proven engine architecture from our small launch vehicle, Alpha, to our Medium Launch Vehicle.”

The next step for Firefly will be a full-duration hot-fire of the Mirdan engine that will last approximately 206 seconds.

As for what’s next for the company, they are targeting a launch in December for Flight 004 of their Alpha rocket that will carry a Lockheed Martin electronically steerable antennae payload demonstrator to low Earth orbit.

If you’d like to see how the Alpha Rockets Reaver engine starts in slow motion, check out this video below!

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Firefly Aerospace conducts first hot fire of new Miranda rocket engine
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