UK 5G reaches new heights in successful flight trials

Just over six months after the consortium won a contract trialling advanced airborne 5G connectivity from a Britten-Norman Islander aircraft, a team of UK companies led by non-terrestrial network telecoms developer Stratospheric Platforms Limited (SPL) has revealed the completion of a series of demonstration flights for the advanced connectivity system.

In 2020, SPL first announced work in the arena as part of a project with Cambridge Consultants, looking to pioneer the concept of using a high-altitude platform with airborne antenna to provide wide-scale coverage of high-performance 5G from the stratosphere from a fleet of zero-emissions aircraft.

The company’s project aims to develop airborne antennae to deliver wide-scale high-performance 5G coverage. Such technology is seen as offering numerous valuable applications, such as quickly restoring networks after major disasters such as earthquakes or tsunamis, where traditional mobile network infrastructure has been disrupted.

Connectivity will be delivered by an unmanned, liquid hydrogen-powered aircraft, designed with a 56-metre wingspan that will, due to its lightweight structure and significant power source, enable a flight endurance of over a week. Britten-Norman is operating the aircraft from its Solent Airport aircraft maintenance (MRO) facility, with the mission to be performed over the North Sea.

The turbine-powered BN2T-4S Islander variant has been selected for the programme due to what is said to be its performance and payload capacity, and the simplicity with which it can be modified to accommodate the equipment. The trial will be conducted under Britten-Norman’s Civil Aviation Authority test conditions.

Britten-Norman is providing key design and trials support for the project, with Marshall Futureworx providing cooling systems technology. A 5G phased array is joined up via a backhaul link to the Adastral Tower in Suffolk, England, from which the comms and mission equipment will operate.

As per schedule, on 18 July 2024, the project team revealed installation of the array under real flight conditions during an event at Britten-Norman’s Solent Airport MRO facility.

The trial, conducted by Britten-Norman’s Flight Test Organisation, aimed to demonstrate the aircraft’s capability to operate safely with the large 5G phased array antenna installed. Key aspects of the flight test programme included assessment of aircraft performance and handling qualities, covering both normal and emergency operation. This will support full certification of the system, enabling integration in terrestrial telecoms networks at connection speeds of up to 200Mbps over 15,000km2.

“Stratospheric Platforms is dedicated to creating pioneering innovative solutions that transform the connectivity landscape,” said SPL CEO Richard Deakin.

“Our commitment to delivering high-altitude, zero-carbon, long-endurance communication platforms will revolutionise how the world stays connected, especially in remote and underserved regions. We believe that our cutting-edge technology will provide unprecedented opportunities for global communication and create a more connected and inclusive world. [The] flight test is an important step in the continuing validation of our technology breakthroughs.”

Garnet Ridgway, Britten-Norman’s head of flight dynamics, said: “It’s always satisfying to deliver a safe and effective flight test programme, but the huge potential of SPL’s system and the collaborative nature of the team made this one particularly exciting. The large and complex nature of the system places significant demands on the host aircraft. However, the BN2T-4S performed admirably; the combination of payload capacity, endurance, climb performance, twin engine reliability, robustness and electrical power generation makes it unbeatable for this mission.”

The next phase of the project will involve demonstrating the technology via a connection to a private UK-based national 5G telecommunications network.