Venus Aerospace’s Rotating Detonation Rocket Engine Completes First Flight Test

May 16, 2025

Venus Aerospace completed the first flight test of its rotating detonation rocket engine in New Mexico on May 14. (Image: Venus Aerospace)

Houston, Texas-based startup Venus Aerospace claims to have completed the first U.S. flight test of a Rotating Detonation Rocket Engine (RDRE) this week. The next generation rocket engine is designed to ultimately enable aircraft to travel "four to six times the speed of sound from a conventional runway," according to an announcement published by Venus after completing the flight test.

Theorized since the 1980s, a high-thrust RDRE capable of practical application has never been flown in the U.S. — and possibly anywhere in the world. According to Venus, the test represents the first flight of an RDRE developed by a U.S.-based company.

Venus's RDRE was launched from a rail at Spaceport America in New Mexico to complete its first flight. On the first flight attempt, Venus’s RDRE successfully launched and flew its engine, validating performance and system integrity under flight conditions. The aerospace startup has released limited information about the test.

“This is the moment we’ve been working toward for five years,” said Sassie Duggleby, CEO and Co-founder of Venus Aerospace. “We’ve proven that this technology works—not just in simulations or the lab, but in the air. With this milestone, we’re one step closer to making high-speed flight accessible, affordable, and sustainable.”

Compared to traditional rocket engines, RDREs offer improved efficiency and compactness, making them particularly suited for advanced aerospace applications. The U.S. Air Force Research Laboratory (AFRL) describes rotating detonation as a “more efficient type of combustion characterized by a closely coupled shock wave and reaction zone, where the fresh propellants are rapidly compressed, heated and burned. Rotating detonations in rocket propellants travel supersonically in excess of 2 km/sec (or 1 mile/sec), with part of the released energy feeding back into the shock wave to maintain continuous operation."

A look at Venus’s RDRE airborne. (Image: Venus Aerospace)

In comparison, traditional rocket engines inject a highly pressurized propellant and oxidizer into a combustion chamber where they burn and generate an energetic exhaust plume.

Venus's website notes that the company is developing its RDRE for a variety of applications to include launch vehicles, satellites and ground transportation, among others. Their engine is designed to be affordable and scalable for both defense and commercial systems, including future vehicles that could fly passengers from Los Angeles to Tokyo in under two hours. The completion of their first RDRE flight test comes a month after Venus provided a program update on the design of their engine and their use of NASA funding to test new nozzle designs — the part of the engine that shapes and directs power.

“This milestone is a testament to what’s possible when engineering rigor meets entrepreneurial urgency,” said Dr. Rodney Bowersox, Associate Dean for Research and Professor of Aerospace Engineering, Texas A&M University. “Rotating detonation rocket engines have been a scientific curiosity for decades. Venus is showing the world that they aren’t just academically interesting — they’re buildable, testable, and operational under real-world conditions. This is how aerospace innovation should look.”

Venus's RDRE is also engineered to work with the company's VDR2 air-breathing detonation ramjet. This pairing enables aircraft to take off from a runway and transition to speeds exceeding Mach 6, maintaining hypersonic cruise without the need for rocket boosters. Venus is planning full-scale propulsion testing and vehicle integration of this system, moving toward their ultimate goal: the Stargazer M4, a Mach 4 reusable passenger aircraft.

“This milestone proves our engine works outside the lab, under real flight conditions,” added Andrew Duggleby, Co-founder and Chief Technology Officer. “Rotating detonation has been a long-sought gain in performance. Venus’ RDRE solved the last but critical steps to harness the theoretical benefits of pressure gain combustion. We’ve built an engine that not only runs, but runs reliably and efficiently—and that’s what makes it scalable. This is the foundation we need that, combined with a ramjet, completes the system from take-off to sustained hypersonic flight.”

Source