Leonardo Proteus

The Leonardo Proteus is an unmanned rotorcraft being built by Leonardo Helicopters for the Royal Navy. This technology demonstrator is currently under development and production at the company’s Yeovil, England facility. Its key feature is a modular payload bay that can be swapped out to suit various missions, including at-sea replenishment and anti-submarine warfare.

In August 2013, the Ministry of Defence awarded a two-year, £2.3 million contract to AugustaWestland (now Leonardo Helicopters) to develop a Rotary Wing Unmanned Aerial System concept, funded through the Anti-Submarine Warfare Spearhead programme. Trials used an SW-4 Solo uncrewed rotorcraft, derived from the PZL SW-4 Puszczyk helicopter. The MOD had previously considered the US Navy’s MQ-8 Fire Scout but rejected it because it “did not meet any endorsed UK capability need.” A second phase contract worth £8 million, jointly funded by Leonardo and the MOD, was signed in 2017 to continue development. In July 2022, a four-year, £60 million contract was signed to build a flyable three-tonne technology demonstrator named Proteus, with work carried out in Yeovil.

The final design was revealed in January 2025. Its airframe is based on the Kopter AW09 single-engine light helicopter, sharing its shrouded anti-torque system and five-bladed rotor.

It carries modular payloads that can be swapped for different missions, such as at-sea replenishment and anti-submarine warfare. Development used a digital twin and artificial intelligence, with over 40 components made from advanced composite materials. While primarily intended for the Royal Navy, the design also focuses on export potential.

Development

On 2 December 2025, Proteus conducted ground-based trials at Leonardo’s Yeovil facility, testing engines, complex systems, and rotor blades in the presence of high-ranking MOD officials and specialists. In January 2026, it completed its first flight from Predannack Airfield in Cornwall. During that flight, it followed a brief test procedure that allowed it to autonomously manage its flying controls without human intervention, while test pilots on the ground continuously monitored it to ensure safety.