This article summarizes reporting by Navy Lookout.

Royal Navy’s Heavy-Lift “Proteus” Drone Clears Major Ground Testing Milestone

The Royal Navy’s ambitious push into autonomous maritime aviation has taken a significant step forward. According to reporting by Navy Lookout, the Proteus Rotary Wing Uncrewed Air System (RWUAS) has successfully completed its ground testing phase at Leonardo’s facility in Yeovil, Somerset. This critical development clears the path for the 2-3 tonne demonstrator to attempt its maiden flight, expected imminently.

The ground testing phase reportedly involved the full engagement of the aircraft’s engine, transmission, and rotor systems while tethered or stationary. These tests are the final technical hurdle required to validate the platform’s safety before it takes to the skies. As noted in the reporting, the Proteus is designed to operate in harsh maritime environments where smaller, lighter drones would struggle, marking a shift toward “heavy” uncrewed systems in the naval fleet.

Technical Validation and Design Origins

The Proteus is not a clean-sheet design but a militarized, autonomous evolution of the Kopter AW09, a single-engine commercial helicopter acquired by Leonardo. By adapting an existing airframe, the program has moved rapidly from contract award to ground running in under three years.

According to details highlighted by Navy Lookout, the system features a five-blade main rotor and is capable of carrying a modular payload of up to one tonne. This heavy-lift capability distinguishes it from smaller surveillance drones like the Peregrine (Schiebel S-100). The aircraft is designed for “plug-and-play” mission modules, allowing crews to swap between anti-submarine warfare (ASW) equipment, such as sonobuoy dispensers, and cargo racks for logistics missions.

Advanced Autonomy

A key feature of the Proteus is its ability to operate without a constant data link to a ground station. Nigel Colman, Managing Director of Leonardo Helicopters UK, emphasized the importance of onboard processing in a statement regarding the program’s progress.

“Proteus is equipped with cutting-edge onboard software capabilities… allowing it to sense its environment, make decisions and act accordingly.”

, Nigel Colman, Managing Director, Leonardo Helicopters UK

This level of autonomy is essential for operations in contested environments where enemy electronic warfare might jam communications between the drone and its host ship.

Strategic Role in the Future Maritime Aviation Force

The Proteus program is a cornerstone of the Royal Navy’s Future Maritime Aviation Force (FMAF) strategy. Rather than replacing crewed helicopters like the Merlin Mk2 or Wildcat, the Proteus is intended to serve as a “force multiplier.”

In an Anti-Submarine Warfare (ASW) role, the uncrewed system can perform the tedious, long-endurance task of monitoring sonobuoy fields, relaying acoustic data back to the ship. This frees up crewed assets for high-complexity tactical decisions and weapon delivery. Captain David Gillett, Head of Maritime Aviation & Carrier Strike for the Royal Navy, described the potential of the platform in recent remarks.

“[It] has enormous potential to shape the Royal Navy’s future hybrid air wing.”

, Captain David Gillett, Royal Navy

AirPro News Analysis

The rapid progression of the Proteus program highlights a broader trend in military procurement: the shift toward “digital twinning.” Leonardo utilized a virtual replica of the aircraft to test flight control algorithms long before the physical prototype was complete. This approach has allowed the Royal Navy to field a heavy-class drone demonstrator in a fraction of the time typically required for aerospace development.

Furthermore, the distinction between “surveillance” drones and “workhorse” drones is becoming sharper. While systems like the Peregrine provide eyes in the sky, the Proteus offers physical mass, the ability to move supplies or drop sensors in Sea State 6 conditions. This capability gap has long been a limiting factor for uncrewed naval aviation, and Proteus appears poised to close it.

Program Timeline and Next Steps

The UK Ministry of Defence awarded the £60 million contract for this phase of the Technology Demonstration Programme (TDP) in July 2022. With ground runs now complete as of December 2025, the focus shifts to the maiden flight.

Following the first flight, the aircraft is expected to undergo a comprehensive flight trial campaign. These trials will test its handling characteristics and autonomous behaviors in real-world conditions, eventually leading to trials at sea.

Sources: Navy Lookout