Project Fresson: Converting The BN-2 Islander For Hydrogen Electric Flight

There are multiple projects within the UK aviation landscape focusing on the transition to net zero emissions for commercial flight.

Aerospace Technology Institute (ATI) with Project FlyZero, the UK government with their Jet Zero Council and Project Fresson, a consortium led by Cranfield Aerospace Solutions which this article is all about.

Rendering of converted Britten Norman BN-2 Islander

Project Fresson, named after Scottish pioneer aviator Ted Fresson, aims to advance de-carbonization of commercial flight – with the ambitious goal to deliver world’s first truly green passenger carrying airline services using hydrogen fuel cell technology.

The project started on October 1st 2019 and is developed by a consortium of industry and research partners: Led by Cranfield Aerospace Solutions, the consortium members include Britten Norman, the manufacturer of the iconic short haul twin engine high wing Britten Normal BN-2 Islander, Innovatus, Ricardo and also Cranfield University.

The plan is to convert a Britten Norman BN-2 Islander to hydrogen fuel cell powered electric flight. The first flight is planned to take place in 2023, with certification and industrialization following afterwards with the goal of having an entry into service in 2025.

I got to fly in the BN-2 Islander many years during a scenic flight over the island of Helgoland in northern Germany and loved the flight, even if it was only a short hope around the airport island “Dune” and Helgoland itself. The airplane is capable of taking off and landing on very short runways, making it an ideal commuter plane for remote channel islands with low passenger counts. Of the 1280 aircraft built up to today, over 400 aircraft are still operated and production is still ongoing. The large amount of flying aircraft makes the type an excellent candidate for a future retrofit program.

We had the chance to talk to Jenny Kavanagh, Chief Strategy Officer and Paul Hutton, CEO at Cranfield Aerospace Solutions. Learn what makes the BN-2 Islander ideal for conversion and how hydrogen generation could be tackled at remote locations.

Project Fresson, a consortium led by Cranfield Aerospace Solutions, is converting a Britten-Norman BN-2 Islander to a hydrogen fuel cell powered electric version. What makes the Islander the aircraft of choice for this project?

The Britten Norman Islander is widely used in operations requiring short flights, particularly around island & remote communities not serviced well by other forms of transport. Its ruggedness & short take off & landing performance allows it to operate in areas where other aircraft cannot. For this reason, it is loved by its operators worldwide and its typical mission (80% of operations being of 1 hour or less), lends itself beautifully to the introduction of zero emissions technologies. Although hydrogen has three times the energy per kg compared to kerosene, it creates challenges with storage as the tanks required to hold the hydrogen have to be pressurised and are heavy. This means when retrofitting the aircraft, the range that the aircraft is actually capable of (up to 1400km with conventional fuel) will be impacted. However, as very few operators use more than a small fraction of this range, a zero emissions solutions solution with a lower range is not problematic. We therefore chose this platform for several reasons:

  • its typical operation doesn’t fight against the restrictions of the technology
  • it is typically operated in island communities awash with green energy, meaning that the potential to create green hydrogen in the local vicinity is less of a challenge as elsewhere
  • the number of these aircraft in service (over 450 worldwide) make the potential market large enough to justify the investment
  • the OEM, Britten Norman, our project partner is fully committed to creating a green version of their aircraft

Once hydrogen fuel cell powered aircraft enter into service, hydrogen needs to be available at remote locations. Is that something you look into at Project Fresson?

It is something that we are working with several operators to investigate, yes. As I mentioned previously, the location of a lot of Islander operators mean that green energy (required to produce green hydrogen needed for the fuel cells) is readily available. Several operators that we are talking to are actively assessing the infrastructure needs and we are supporting them in that endeavour. More and more governments, including the UK, Europe and the US have recognised the need to create the necessary infrastructure which will be the key to ensuring a long-term solution for the operation of these aircraft.

Cranfield Aerospace Solutions are also a member of Project NAPKIN, a Future Flight consortium including Heathrow, London City and Highlands & Islands Airports, part of which is investigating this topic.

These aircraft will need around 34kg of hydrogen for a one hour flight so the supply needs are not overly demanding – a small on-site electrolyser can use locally available green electricity to make green hydrogen,  or even delivery of the hydrogen by truck (where possible) would suffice to start with, which reduces the challenge.

The other key aspect is the ability of airports and maintenance organisations to handle hydrogen in a regulated environment; an aspect often overlooked. We are working very closely with our airport partners as they liaise with the regulatory authorities to understand what regulations will need to change and how the introduction of hydrogen will impact their operations.

Your mission statement is to accelerate the transition to net zero emissions in regional air travel. Can you outline your plans after a successful conversion of the Islander?

The development of a 9 seat hydrogen aircraft is a vital first step in the journey to net zero aviation, and it will be a technical and commercial success in its own right. However, CAeS has ambitions to build on that success and to move onto larger aircraft requiring greater range – first 19 seat and then moving to larger regional aircraft of 50-100 seats.

Currently we are focussing on the propulsion system integration as the development of the systems technology is critical to enabling future aircraft. Our ambition is to use the learning from this phase to scale up the propulsion system to one powerful enough and with the range to offer a 19-seat solution.

Once that is developed, we intend to design a new 19 seat aircraft that will be optimised for the larger propulsion system; to get the best out of this new technology, any solution will need to be a combination of aircraft and systems design.

We are currently analysing the likely requirements for a 19 seat zero-emissions aircraft to assess the best design solution for that future market. As with the Islander development, the solution presented must be commercially viable, not just physically possible, and therefore a deep understanding of the market, technical and safety requirements is essential. This is where our core capabilities lie; converting requirements into an aircraft concept, be it retrofit or new, assessing suitable technologies to select the best one for the platform & mission.

Are you currently hiring for Project Fresson and if so, what roles are you trying to fill?

Yes absolutely, we’re growing fast and have continued to recruit, even through the COVID period. We encourage talented people with a motivation to challenge themselves, grow and to be part of a passionate and diverse team to get in touch.

All of our open positions are on our website at

We’re recruiting a wide range of roles from supply chain, facilities, aircraft propulsion engineers, air vehicle designers, systems engineers and structural/mechanical engineers.

If you have any readers interested in joining our team, we encourage them to please take a look at our website & get in touch with us. We’d be delighted to hear from them.

Thank yo for your time.