Firefly Space Systems Completes Successful Mission Duty Cycle Tests

An MDC test of the Firefly Alpha combustor performed in Cedar Park, Texas. (Image courtesy of Firefly Space Systems.)

Firefly Space Systems recently enjoyed a milestone by successfully completing over 50 hot fire tests of its engine combustor. This includes multiple full mission duty cycle (MDC) tests, which cover the entire 163 seconds required for the first stage of Firefly’s rocket, called Alpha. Firefly is a relatively new player in the commercial space industry, following the likes of more well-known companies like SpaceX and Blue Origin.

The Firefly combustor will be used to power both the first and upper stages of Alpha, a rocket designed with the goal of offering low-cost small satellite launches. The first stage (FRE-2) utilizes an array of twelve combustors in what’s called an aerospike configuration, whereas the second stage (FRE-1) utilizes an engine with a single combustor. And yes, I know that’s a confusing naming convention.

Alpha is designed to carry a payload of 200 kg, and is powered by Lox/RP-1 propellants. The second stage engine FRE-1 produces a thrust of approximately 27.5 kN, and the first stage FRE-2 produces approximately 443 kN. To put those numbers on a scale, SpaceX’s recently announced Mars vehicle will have a lift-off thrust of 128 MN (though that’s not exactly a fair comparison). Nevertheless, the engines will be powerful enough to launch the small satellite payloads into low earth orbit.

An aerospike configuration of twelve combustors arranged in an annular ring. (Image courtesy of Firefly Systems.)

"These tests of our combustor retire critical engine design risk elements and place Firefly among an elite group of NewSpace companies that have successfully performed an MDC hot fire on a flight weight combustor,” said Firefly CEO Thomas Markusic. “We have shown that our regeneratively cooled engine is capable of withstanding the stresses associated with long duration hot fires."

In spite of the success of the hot fire tests, Firefly is in a bit of a surprise financial crisis. Whatever becomes of the company, it’s undoubtedly earned applause for an incredible display of engineering.

For more rocketry news, read about NASA’s successful test of the SLS rocket.