Cranfield Aerospace Solutions (CAeS) has received a £9-million (US$11.6-million) grant to convert a Britten-Norman (B-N) Islander into a hybrid-electric aircraft. As part of Project Fresson, the goal is to produce an environmentally friendly propulsion kit that can be retrofitted into the world's fleet of the nine-seater island hoppers that number in the hundreds.

Electric propulsion for aircraft is a technology trend that promises greener air travel with much lower emissions per mile. However, the current state-of-the-art means that electric aircraft often have restricted ranges and payloads.

Named after Scottish air pioneer Ted Fresson, Project Fresson, in the near term, works into these short ranges rather than against them. In fact, the project was inspired by the needs of Scottish airline Loganair, which operates in the Orkney Islands and is famous for having the world's shortest regular-service flight, which goes from Westray to Papa Westray in 1.5 minutes. The hope is that retro-fitting such short hoppers would not only cut emissions and noise, but also reduce maintenance costs.

The 30-month Project Freeson is led by Cranfield and includes several partners across Britain. Rolls-Royce is providing the power-management system, the Denis Ferranti Group is making the electric motors, Delta Motorsport is building the battery packs, with the University of Warwick doing the battery testing. Meanwhile, Britten-Norman is supplying the Islander aircraft and Cranfield University is studying key technologies.

The first version of the system is to be built from off-the-shelf parts and the first prototype could fly in 2021, followed by production versions by 2023. Under batteries, the retro-fitted Islander will have a range of 60 minutes with a 30-minute reserve – longer using a backup twin-piston engine, which may be replaced by an M250 turboshaft in later versions.

Once the prototype demonstrator takes to the air, Cranfield will seek EASA certification, which will allow the partners to market the retrofit kits. This will be followed by development of a similar kit for a current 19-seat sub-regional aircraft and the design and building of an all-new 19-seat aircraft.

The new grant was from the British government's ATI Programme that is tasked with bolstering the country's position in the civil aerospace field.

"The results of this exciting electric aircraft demonstrator project can be rapidly developed into an EASA/CAA (European Aviation Safety Agency/Civil Aviation Authority) certified modification kit, enabling the UK to lead the way with the first passenger-carrying sub-regional aircraft capable of all-electric flight," says Paul Hutton, CAeS CEO. "The strength of the industrial partners involved in this project, are underpinned by the world-class aerospace/manufacturing research capabilities of Cranfield University. This is going to accelerate our green transport revolution."

Source: Cranfield Aerospace