Aviation startup Hermeus has completed ground testing of its first fully integrated vehicle, Quarterhorse Mk 0. This non-flying prototype acted as a ‘dynamic iron bird’ for the company by validating all major aircraft subsystems in a real-world environment.
The Mk 0 is the first of four aircraft planned for the Quarterhorse program. Hermeus hopes that this program will eventually lead to the development of an aircraft that can surpass the SR-71’s absolute speed record for a crewed air-breathing aircraft, which was set at 2,193.2 mph on July 28, 1976. However, it’s important to remember that the Quarterhorse is uncrewed, so the idea of “beating” that longstanding record may not be entirely accurate.
Hermeus’ ultimate goal is to achieve hypersonic speeds, which are typically considered anything above Mach 5. Each aircraft will progressively increase in complexity, allowing Hermeus to distribute program risk across multiple vehicles and accelerate learning.
The company says the Quarterhorse Mk 0 was designed and built in just six months and that all its test objectives were completed in 37 days of testing.
Among the objectives completed were:
- Demonstrating remote command and control taxiing
- Evaluating radio frequency (RF) latency and ground handling qualities of the integrated systems
- Demonstrating proper state of the vehicle and Flight Deck during lost link
- Demonstrating human factor evaluations and pilot-in-the-loop steering & controls
The testing took place at the Air Force’s Arnold Engineering Development Complex (AEDC) in Tullahoma, Tennessee. This decision allowed the team to directly interface with the Air Force range and regulatory authorities.
“This was the first time our Flight Test team had an opportunity to work in a deployed test campaign with external stakeholders,” said Hermeus Vice President of Test, Don Kaderbek. “The more the team works together and establishes their battle rhythm, the smoother flight testing will go.”
The development and testing of Quarterhorse Mk 0 align well with Hermeus’ core tenets of hardware richness and rapid real-world testing.
“Leveraging rapid and iterative design is how Hermeus will accelerate aircraft development on timelines that are relevant to our customers,” commented Hermeus CEO and co-founder AJ Piplica. “Test campaigns measured in days instead of months or years represent the pace required to mature hypersonic technology and field transformative aircraft.”
Hermeus’ first flight vehicle, Quarterhorse Mk 1, is actively being built and scheduled to fly in 2024. The Mk 1 is not intended for high-speed flight trials but rather remote takeoff and landing testing. The Quarterhorse Mk 2 will be responsible for supersonic speeds below Mach 3, while the Quarterhorse Mk 4 is expected to reach speeds beyond Mach 3 and break the all-time airspeed record held by the SR-71, demonstrating turbojet-to-ramjet mode transition in flight.
