Tiny but powerful Mach 5 ramjet engine could make drones supersonic soon

An Ohio-based startup, Velontra, has successfully tested its five-foot-long hypersonic engine that can achieve speeds of Mach 5.
Christopher McFadden
Testing the small hypersonic turbo-ramjet.
Testing the small hypersonic turbo-ramjet.


A small Ohio-based startup, Velontra, has reported the successful testing of its small hypersonic turbo-ramjet. The tests were conducted inside Purdue University’s wind tunnel, and the engine is described as a "first-of-its-kind." The incredible engine developed can deliver thrust at over five times the speed of sound, which is greater than Mach 5!

“It is powerful, small, and anything but tame. It is ready to buck the system. We sent it through a wind tunnel at Purdue University at speeds over Mach 4.5 and altitude simulated over 100,000ft, and it successfully screamed through vigorous testing with flying colors,” said Velontra CEO Robert Keane III.

Tiny but powerful Mach 5 ramjet engine could make drones supersonic soon
Velontra Bronco engine.

The engine is small but powerful

The engine measures 11 inches (28 cm) in diameter and is five feet (1.5 meters) long. According to Velontra, the cost of a Bronco unit will be "less than $200,000". The company was established with affordability and speedy development as top priorities, drawing inspiration from SpaceX, as stated by Velontra's CTO, Joel Darin.

“We don’t want to just ask investors to trust us with a ton of money and ten years later see if our idea works or not. We want to produce actual products at each stage that develop the technology we’ll eventually need. This small application lets us develop a product at a fraction of the cost [of full-scale hypersonics] that people will buy,” Darin explained.

Darin mentioned that conducting extensive hypersonic propulsion system tests in full-scale wind tunnel facilities can amount to a whopping $50,000 per hour. “We’re paying $300,000 to get two to three months of testing,” he says. “The development is much cheaper, but the lessons we learn are scale-able to bigger applications,” he added.

Velontra intends to incorporate the Bronco hypersonic propulsion system into compact drones, enabling them to reach supersonic speeds for commercial and military purposes. Additionally, the company has outlined its intentions to construct an unmanned spaceplane to serve as a satellite launch platform.

“We have more than doubled our company size in the last six months, and our scientists/engineers have advanced Velontra’s hypersonic propulsion system, making our technology a premier market leader in the US as we compete with the hypersonic capabilities of China and Russia,” said Keane.

It can reach Mach 5

The afterburner technology allows for high speeds of over Mach 2 without any increase in drag. This speed is further increased to over Mach 5 when in ramjet mode. According to Joel Darin, the Chief Technology Officer of Velontra, their propulsion system is state-of-the-art and provides advanced capabilities and applications that were never possible before.

The Bronco propulsion system will power Velontra's hypersonic aircraft. This cutting-edge prototype is set to revolutionize Velontra's Space Plane and make Low Earth Orbit travel more efficient and reliable.

According to Derin, Velontra's next step is to enhance Bronco's performance by focusing on aspects such as thrust, thrust vectoring, and durability, aiming to achieve its first flight in the Venus Aerospace UAV. Successful progress in these areas could lead to increased interest and funding for the company.