• The future of human aviation is hypersonic flight (speeds greater than Mach 5).
• Engineers must create hybrid engines that can operate at subsonic, supersonic, and hypersonic speeds to achieve that goal.
• Hermeus, an aviation company, successfully transitioned the Air Force's Quarterhorse hypersonic aircraft's turbojet engines to ramjet engines.

Introduction

Introduction to Hermeus

The SR-71 Blackbird is one of the few planes that makes aviation geeks feel as amazed and excited as no other plane. It doesn't help that the Blackbird is the fastest air-breathing (also known as "not a rocket") crewed aircraft in the history of human aviation, but the fact that it was designed to be stealthy and that its past is shrouded in secrecy certainly doesn't hurt the Blackbird's reputation for coolness.

The SR-71, which has the ability to fly at speeds greater than Mach 3.2 (approximately 2,200 miles per hour), has been considered the fastest aircraft in the world for the better part of the past half a century.

However, the aviation company Hermeus, which is based in Atlanta, believes that it is time for some healthy competition.

Overview of a Difficult Piece of Aviation Engineering

The company came up with the idea of "hypersonic flight," in which a plane moves at a speed faster than Mach 5, and it is not limited to being used only for secret intelligence gathering. This is because Hermeus plans to bring hypersonic planes to a nearby airport in the near future.

In 2021, the United States Air Force awarded Hermeus a contract worth sixty million dollars to construct three unmanned concept planes. One of these planes, known as the "Quarterhorse," was capable of traveling at very high speeds.

Chimera, a hybrid turbojet-ramjet engine, was successfully fired for the first time by Hermeus at the tail end of the previous year, marking a significant advancement in the company's efforts.

How Hermeus Has Figured Out the Difficult Piece of Aviation Engineering

The Difficulties Faced

The powerful SR-71 has a Pratt & Whitney J58 turbojet engine that gives it a top speed of about Mach 3, making it a scary monster that eats air. 

Hermeus's hypersonic design is turned on by a ramjet, which can only work at high speeds because it uses this air to pressurize air and fuel in the combustion chamber. This kicks in Hermeus's design and moves the imaginary Quarterhorse aircraft to speeds of Mach 5 and faster. 

Ramjets can only operate at high speeds because they use this air to pressurize the air and fuel in the combustion chamber. If an airplane wants to compete with the Blackbird, its engine must be able to switch between turbojet, ramjet, and turbojet operation without any problems. 

Hermeus has already figured out how to do the difficult piece of aviation engineering that needs to be done.

Hermeus’ Solutions

Glenn Case, the co-founder and chief technology officer of Hermeus, was recently featured in a video where he talked about the company's recent achievement of demonstrating "a mode transition." This means that the company switched from turbojet mode to ramjet mode. It is safe to say that this is the obstacle that must be overcome before hypersonic flight can become a reality.

Hermeus needed to simulate the high-speed pressures of Mach 4 flight in order to test its Chimera engine, so the company packed up its engine and sent it to the Notre Dame Turbomachinery Lab, which is a high-speed Mach test facility.

Once the engine was there, Hermeus was able to test its Chimera engine. There, Hermeus showed how the Chimera could switch between its engines by sending high-speed air around the turbojet and into the ramjet.

The hypersonic engine that will be used in Quarterhorse is one of several projects currently under development that are working toward the goal of making hypersonic flight a reality. Among these projects is the one known as "Project Mayhem," which is being carried out by the United States Air Force.

Impact of Hermeus’ Achievement

Future Goals of Hermeus

The goal of this project is to design a hypersonic bomber that will be ready in the not-too-distant future.

In other words, how close are these hypersonic planes to actually taking off?

In October of 1958, Pratt & Whitney conducted the first test of the J58, and by October of 1962, the SR-71 was tearing across the sky. This would seem to indicate that history is a reliable indicator.

Benefits to the Aviation Industry

On the other hand, the J58 was nothing more than an improved and more powerful version of a technology that had previously been developed.

Conclusion

Summary of Hermeus’ Achievements

On the other hand, Hermeus and other hypersonic companies are focusing their efforts on developing a hybrid platform that is more complicated.

Hermeus says it is on track to beat the Blackbird's "outright air-breathing aircraft speed record" in the coming year, according to New Atlas. For the record, this information is being provided here.

Who could possibly say? It's possible that by the end of this decade, human aviation will finally be able to enter the era of hypersonic flight. On the other hand, the J58 was nothing more than an improved and more powerful version.