Islander Arrives For Modification To Hydrogen Propulsion

To be modified to fuel-cell propulsion, the ex-Skybus Islander will re-register G-HYUK for Hydrogen UK.
Credit: Isles of Scilly Steamship Group

Cranfield Aerospace Solutions has taken delivery of a Britten-Norman BN-2B Islander for conversion to zero-emission hydrogen-electric propulsion.

The nine-passenger aircraft has been acquired from Isles of Scilly Steamship Group under the UK government-backed Project Fresson.

One of four Islanders operated by Isles of Scilly Skybus for cargo and medical flights, the aircraft–now based at Cranfield Airport in England–will be test flown first to measure baseline performance with the existing Lycoming O-540 piston engines.

A consortium led by Cranfield Aerospace Solutions (CAeS) will then retrofit the Islander with a pressurized-hydrogen fuel-cell propulsion system. Flight tests with the new power train are planned to begin in the first quarter of 2023.

Project Fresson is being supported by the UK government with a £10.3 million ($14.3 million) grant via the Aerospace Technology Institute. CAeS is working with Ricardo UK on fuel cell system development and Innovatus Technologies on the hydrogen fuel tanks.

The project’s goal is to have a certified system on the market for the Islander in 2025, both as a retrofit and in a new model of the aircraft from Britten-Norman. This constitutes the funded Phase 1 of Project Fresson. Planned later phases would develop hydrogen-powered 19-seat and 75-seat regional aircraft.

Under another UK government-supported hydrogen aircraft project, startup ZeroAvia has placed an order with Hyzon Motors to deliver a high-performance lightweight fuel cell for evaluation. U.S.-based Hyzon makes fuel-cell-powered heavy trucks and buses.

According to Hyzon, the company’s next-generation Gen3 fuel-cell stack has a gravimetric power density of more than 5.5 kW/kg, “well above industry averages.” This is achieved through improvements to the bipolar plate and membrane electrode assembly in the fuel cell, the company said.

ZeroAvia will test the fuel-cell stack through simulated aircraft duty cycles. Once the system is validated on the ground, the next step would be to test it in flight, Hyzon said. 

ZeroAvia already has a contract with U.S. startup HyPoint to deliver a turbo air-cooled fuel-cell system for demonstration by the end of 2022. HyPoint says its initial fuel cell has system-level specific power of 2 kW/kg and it has research underway to achieve 4 kW/kg.

Under the UK-supported HyFlyer II project, ZeroAvia is developing a 600-kW hydrogen-electric propulsion system for 19-seat regional aircraft. Flight testing in a modified Dornier 228 is planned to begin this year, aiming for certification and market availability in 2024. ZeroAvia has also begun development of a 2-megawatt power train for 50-plus-seat regional aircraft, aiming for 2026.

Graham Warwick

Graham leads Aviation Week's coverage of technology, focusing on engineering and technology across the aerospace industry, with a special focus on identifying technologies of strategic importance to aviation, aerospace and defense.