Hermeus Rolls Out First Quarterhorse Hypersonic Test Aircraft

The Quarterhorse Mk 1 sits on the runway at the Hermeus facility in Atlanta, Georgia, where the company revealed its first operational uncrewed test aircraft. (Image: Hermeus)

Hermeus has unveiled its first aircraft — Quarterhorse Mk 1 — which will take flight later this year.

Quarterhorse Mk 1 is the Atlanta-based startup's first operational test vehicle for its hypersonic aircraft development program. The uncrewed aircraft is powered by a GE J85 engine and has been tasked with demonstrating autonomous takeoff and landing with near-hypersonic speed by 2026. Flight testing will occur at Edwards Air Force Base.

"We designed and built this airplane - from scratch, like literally napkin to airplane - in 204 days. Let that sink in. 204 days. The standard here is about 1,400 days - 3.5 years. We missed the P80 record by 61 days," AJ Piplica, CEO and Founder of Hermeus said in a post  to his X account on the day of the Quarterhorse MK 1 reveal.

Designed, built, and integrated in just seven months, this is the company’s second fully-integrated vehicle in the past year, following Quarterhorse Mk 0 which completed its test campaign in November 2023. This rate of iteration represents a new standard of one aircraft per year, which the team has set for the future pace of aircraft development.

This milestone marks the transition from the design and build phase to the integrated test phase for Mk 1. The coming months will see the vehicle endure a battery of tests across its subsystems, ground station, operations, and human factors to prepare it for flight testing.

“Moving into the integrated test program is the culmination of a huge team effort and a significant emotional event for the entire company,” said Hermeus Vice President of Test, Don Kaderbek. “As we begin the journey to first flight, we will conduct a comprehensive evaluation of the aircraft’s performance while simultaneously examining the effectiveness of our test procedures, safety culture, and interdisciplinary team collaboration. We’re excited and humbled to conduct this testing at the legendary Edwards Air Force Base.”

Hermeus plans to start flight testing the uncrewed hypersonic test vehicle at Edwards Air Force Base, starting this summer. (Image: Hermeus)

Each aircraft in the Quarterhorse program progressively increases in complexity, building on the learnings of prior builds. This approach manages program risk across multiple vehicles and accelerates delivery of products and services to Hermeus customers.

“The most unique and important aspect of our approach to developing a hypersonic aircraft is our rate of iteration – designing, building, and flying an aircraft in less than a year, every year,” Piplica said. “It’s a pace that hasn’t been seen in the aircraft world for half a century. This approach has been proven successful in delivering massive improvements in the capabilities of rockets, satellites, and small drones. We’re now bringing that power of iteration speed to aircraft. It’s a capability that is absolutely necessary for solving the challenges of operationalizing hypersonic aircraft.”

The Hermeus unveiling is one of the latest hypersonic advancements for the aerospace and defense industry, following the recent test flight of Stratolaunch's Talon-A hypersonic vehicle, which reached near hypersonic speeds during a March demonstration flight at Mojave Air and Space Port, California.

In addition to showcasing the aircraft, Hermeus also shared plans for the next iteration of Quarterhorse – Mk 2 – which will feature the Pratt & Whitney F100 engine and fly at supersonic speeds next year.

Hermeus’ strategic decision to transition to the more capable F100 engine for Quarterhorse Mk 2 accelerates the company’s roadmap to Darkhorse, a multi-mission hypersonic aircraft for defense and national security missions.

“This upgrade is a huge win for getting a high-performance aircraft into the hands of customers sooner and shows the power of the fast and iterative approach at Hermeus. By breaking free of rigid, multi-year development timelines, we are enabled to build the right aircraft for this moment and get that aircraft in the air in less than a year,” commented Hermeus COO and Co-Founder, Skyler Shuford. “Mk 2 will be our third sub-year aircraft system build, and while we still need to prove ourselves in flight, an enormous amount of programmatic risk is reduced by having the next airplane closely following.”