Hermeus’ Hypersonic Flight in a Movable Building at PDK Airport

GA – Have you heard of Hermeus? Hermeus was founded in 2018 and develops hypersonic turbojet-ramjet engines. These advanced, hybrid engines are being developed in order to build hypersonic commercial and military aircraft. Hermeus’ headquarters is located in Atlanta, GA, and their propulsion testing facility is located at PDK airport. Along with their Atlanta locations, they also have offices in Washington DC and Los Angeles. Currently, they are working on four projects, including the Chimera, Quarterhorse, Darkhorse, and Halcon.

The Importance of Supersonic Flight

Today, passengers who need to fly internationally often face long flight times of seven or more hours. Now, imagine traveling from the United States to Europe in less than two hours. Supersonic aircraft can make this intercontinental traveling dream a reality, and one of Hermeus’ designs, the Halcyon, is anticipated to be able to make the flight from New York to Paris in an hour and a half. Imagine how that would change business and leisure travel. Vacationers and executives could depart for Paris after breakfast and land in time for lunch.

Hermeus at Peachtree Dekalb Airport (PDK)

Hermeus’ primary location is in Atlanta, and their engine testing is performed at Peachtree Dekalb Airport (PDK). The airport rightfully boasts that it is the gateway to the south, and it’s no surprise that Hermeus chose it. PDK airport provides 7,300 jobs while having an estimated income of 130 million. The airport conducts 230,000 operations per year and sits on 745 acres. PDK has four runways, including Runway 2R/20L, Runway 16/34, Runway 2L/20R, and Runway 9/27, and Hermeus’ mobile engine testing facility sits next to one of those runways.

Hermeus: An Innovative Company with an Innovative Building

Hermeus’ engine development and testing site at PDK is an environmentally friendly marvel. Here at APN, we were lucky to be able to have our affiliates in Georgia, Jim Flock and Rachael, tour the facility, and they had an amazing adventure.

The entire two-story facility is constructed out of stacked shipping containers because it’s located right next to the runway. The location is ideal for Hermeus so that they can easily test their new hybrid engines. However, it came with challenges. Permanent buildings can’t be located that close to the runway. Therefore, Hermeus needed to come up with a temporary yet comfortable and productive building design. That led to the development of a two-story shipping container testing facility. If, at any point, that building needs to be removed, cranes can be brought in to move the individual shipping containers. Of course, this means that the design and testing facility is also environmentally friendly. It’s powered by solar and hydroelectric generators, and the bathroom facilities are connected to an aboveground septic tank.

Now, imagine working on state-of-the-art airplane engine technology that’s designed to propel an aircraft through the sky at Mach 5 in a building that is self-sufficient and movable. That’s taking sustainability and innovation to the next level.

Hypersonic VS. Supersonic Speed

Now, you may have heard of supersonic flight, which occurs anytime an aircraft flies above the speed of sound, which is 761.2 miles per hour or Mach 1. Hypersonic speed is five times the speed of sound or 3,806 miles per hour (Mach 5). Hermeus isn’t just designing supersonic engines, like the ones used to power the Concord, it’s designing engines that are capable of flying at hypersonic speeds. Flying at Mach 5 is predicted to completely change the commercial flight experience. Not only is it predicted to be fast, the flights are predicted to be so smooth that passengers won’t even feel like they’re flying.

Hermeus and Hypersonic Speeds

Inside the engine testing facility, Jim and Rachael had the opportunity to view the design and testing areas up close. They spotted many of Hermeus’ staff members working on computers and examining and testing engine components. In fact, Hermeus’ need for computer processing is so great that they have an entire room dedicated to it.

Hermeus has the ability to test the engines inside the building and outside. When they test an engine inside the facility, the engine is given fuel, and there’s water on standby. The goal is to rev these engines up to see how much power they can produce. If those engines happen to overheat, there are nozzles that spray water onto the engine to help cool it down quickly and prevent damage.

Periodically, they’ll also take an engine out of the facility and place it on the runway for testing. When Hermeus decides to test an engine, they have to call the tower first. This is because the engine could produce excess noise, and the air traffic controllers and aircraft in the area need to be aware of it.

What Is Hermeus Working On?

Hermeus has four projects in its pipeline, including:

• The Halcyon – Designed to be the future of passenger air travel. This hypersonic jet will be designed to reach speeds of Mach 5.
• The Darkhorse – Designed to be a hypersonic unmanned aircraft for military use.
• The Quarterhorse – Designed for engine and hypersonic speed testing with the hopes of breaking the airspeed record. They unveiled the Quaterhorse MK-1 in March 2024.
• The Chimera – Hermeus’ hybrid engine. This engine is comprised of a turbojet and a ramjet.

The Chimera Hybrid Engine

When you think of hypersonic speeds, you probably envision a rocket, and rockets are useful for blasting flying vehicles across great distances and even into outer space. However, Hermeus realized that there’s a need for a jet engine that operates at both low and high speeds. The Chimera engine consists of both a traditional jet engine and a ramjet. The jet engine operates at lower speeds. At higher speeds, the ramjet propels the engine. This will allow hypersonic aircraft to maneuver safely through a range of speeds.

With all this innovation, we expect Hermeus to continue to do well and develop more hypersonic engines and airplanes. Our two affiliates, Jim and Rachael, were certainly impressed with everything they saw at the engine testing facility.