The shift toward hybrid electric propulsion (HEP) systems in aviation is primarily driven by advanced battery technologies with higher energy densities, enhanced safety features and improved charging capabilities. This research provides a comprehensive market analysis to identify current trends, challenges and opportunities in battery development for electric aircraft. Emerging technologies, such as solid-state batteries, are also highlighted for their potential to revolutionize the market. This study aims to align research efforts with industry needs, contributing to the advancements in battery technology critical to supporting HEP and paving the way for a more sustainable future in aviation.

The presentation will comprise an introduction to the UK CAA Hydrogen Challenge, its aims and objectives, gap analysis for certification specifications, sandbox activities and working groups.

In this era of rapid technological advancements, the aviation industry faces a significant sustainability challenge. This presentation explores the critical role of fleet flexibility in adopting new, more efficient technologies amidst uncertainties in certification and market readiness. It examines the need for adaptable business models to integrate novel aircraft while maintaining profitability and meeting customer demands. Special emphasis is given to the dynamics between regional and larger commercial aircraft, drawing insights from innovative business models and implications for aircraft economics and fleet renewal strategies.

The aviation sector is undergoing a tremendous change, driven by the need for decarbonized air mobility. Electric propulsion changes the paradigm not only in the air but on the ground. While traditional OEMs were making planes, counting on the availability of fuel, today's need for charging an aircraft brings a serious topic to the table, and the electrification of airports and vertiports means a total shift in energy transition, from the source of energy all the way to its management and final delivery.

To reach the Air Transport Action Group (ATAG) goals aimed at stabilizing CO2 emissions and reducing net emissions from air travel, Airbus is investing its research efforts in electrification by exploring some of the key technologies of hybridization such as e-motors, power distribution, motors controllers and new architectures. In this journey, the Sustainable Water Injecting Turbofan Comprising Hybrid Electrics (SWITCH) project aims to answer the challenge of climate-neutral short-medium range air transportation by developing a revolutionary sustainable gas turbine propulsion system – combining hybrid electric propulsion with water-enhanced turbofan (WET) technologies with Pratt & Whitney’s GTF engine architecture.

We need to rethink aviation, integrated and with our own energy ecosystems. Evia Aero strives to be the first airline in Europe to operate zero-emission aircraft on a fixed, commercial schedule. Operations are scheduled to start in late 2026/early 2027 with a 9-seat hydrogen-electric aircraft (H2 converted Britten-Norman Islander) followed by a 9-seat battery-electric aircraft (Eviation Alice) in 2029. Evia Aero is one of the aviation companies in Europe that has signed LOIs for 25 electric aircraft (manufacturer Eviation, USA) and 25 hydrogen hybrid aircraft (manufacturer Cranfield Aerospace Solutions, UK).

Per airport, the potential of e-flight could be investigated based on the current and future demand and route network. Furthermore, the additional charging and electrical infrastructure could also be quantified based on earlier research. This case study based on the Costa Rican market combines these two initial steps and continues with an analysis of the route economics. With this third step, new insights have been gained, into which factors have a significant influence on the economic viability of e-flight. Consequently, it shows the influence on the year in which e-flight would show lower operating costs than conventional flights.

The presentation offers a scaleable airport system-level energy model developed to represent the electrification of the ground support equipment (GSE) fleet of a regional airport, combined with the electrification of short-range flights. The model is capable of calculating and visualizing the airport electrical loads from future electric ground support equipment (eGSE) in combination with the electrification of short-range flights scheduled from the airport. The work has generated the requirements for future electric loads at an airport and the effect on the electrical grid infrastructure which needs to be in place to support this future electrification and decarbonization opportunity.

This presentation shows potential scenarios for the infrastructure expansion of a regional airport during the transition to the electrification of aviation. With a real-time simulation model, accurate data from two regional partner airports and hybrid-electric aircraft designs of a 50-pax regional aircraft class, realistic statements can be made on a development trend for airports. In particular, the potential expansion of the electrical infrastructure through PVs, wind farms and on-ground battery storage systems is analyzed. The simulation can show the energy requirements and which operating strategies could be of interest to airport operations in the future.

The strength of hybrid systems is their ability to adapt the system architecture to meet specific platform needs. P&W, along with its RTX partners, is developing the key building blocks to meet the needs of over 100 unique platform requirements. Learn about how P&W is doing this and the challenges it is tackling along the way.

The presentation will offer an overview of clean aviation projects with Fraunhofer IISB participation. Project Newborn focuses on the development and demonstration of the TRL 4 ground demonstrator of a complete propulsion system using 1MW fuel cell modules for electricity generation. Project Amber research efforts will lead to tests of a ground-mounted rig that combines a megawatt-class electric motor driven by hydrogen fuel cells. Project HyPoTraDE will design, assemble and ground-test a set of 500kW modular fuel cell battery hybrid electric DEP powertrain architectures. The HeDrive project: presentation of the demonstrator of a fail-redundant 700kW electric helicopter propulsion system.

The safety of electrical propulsion systems for aircraft is achieved by a totally different route from conventional aircraft. It is essential that safe design is designed-in from the beginning as adapting the design afterward simply will not work. The paper describes the design principles used on the GKN-led H2GEAR program and how these are being demonstrated to certification authorities. This consists of a radical design approach using advanced protection systems that can be shown to give a system that is as least as robust as that used in conventional large aircraft. The presentation will detail this design and the results obtained.

The ATI has published the UK Aerospace Technology Strategy, Destination Zero and continues to support technology development in the UK to make this vision a reality. Part of this future vision includes more electric and hybrid aircraft. This presentation will provide an update on some of the key ATI-funded projects that are making ultra-efficient and zero-carbon aviation a reality. Additionally, a summary of the technology bricks that ATI has identified as the key drivers toward hybridization in aviation will be shared and discussed.

Julian Renz will discuss ZeroAvia's path to commercializing hydrogen-electric aviation. Apart from progress on the company's core engine offering, Renz will discuss the recent interest in ZeroAvia's components from other stakeholders, and how collaboration in the ecosystem can deliver the most practical path to zero-emission aviation.

Zero-emission mobility as a common goal across industry – whether on the road, in the air or in space – motivates us to develop advanced automotive-based solutions for the future of mobility. In the area of propulsion, the presentation focuses on the impact of advanced powertrain technologies (hybrid, hydrogen, electric) in the mobility future. Beyond the powertrain-proven industry solutions from components, technologies and engineering, the presentation will share Bosch's experience and expertise of security and safety-related products and services for aerospace. Bosch believes that it is key to utilize synergies across industries to speed up and enable the technological transition.

Several technologies have the potential to decarbonize aviation – sustainable aviation fuel (SAF), hydrogen, or even direct air capture with carbon storage (DACCS). However, this is not a straightforward choice: SAF faces challenges in affordability and scaling up, hydrogen requires significant changes to aircraft technologies and infrastructure, whilst DACCS is an out-of-sector solution that still relies on fossil fuels. Roland Berger and NLR team up to assess this problem holistically by analyzing the ecosystem economics and environmental lifecycle impacts of these technologies.

Certification of propulsion batteries and high-voltage systems.

Targeted entry into service (EIS) for different classes of vehicles will be projected along with the performance requirements needed to be achieved. Various obstacles for a speedy EIS will be analyzed. Based on the latest technical achievements, methodologies will be presented for rapid acceleration. Faster TRL progress, analysis, design, testing, fabrication, certification and infrastructure will be proposed. New tools using artificial intelligence and machine learning will be introduced. Autonomous vehicle function will be addressed as a provision for time saving. Hardware-in-the-loop will be included as well. Conclusions and recommendations for a faster EIS will be stated.

Aerospace projects imply multiple layers, objects and relationships. Their combined content and interconnections generate a ramping complexity as the project grows, requiring increasing assessment and reporting capacities. The presentation will discuss how a continuous monitoring solution following the project lifecycle can help track software quality and standard compliance at the global level as well as applying full traceability analysis to focus on individual objects needing attention.

This presentation will overview the infrustrcture and test processes needed to develop, characterise and qualify electric propulsion systems for flight. It will first review test requimrements needed as part of the development procss and specific facilites required. It will then cover subsystem and system test requirements including fault insertion. A detailed overview of the investments at the University of Nottingham's National Electrification Propulsion Facility will given, including the recent developments in a MW-class cryogenic powertrain testing facility. The presentation will also cover digital twins for HIL tests and a number of case studies will be presnted.

NLR will give an overview of its activities in the EU Clean Hydrogen project COCOLIH2T. Under this project, NLR and its partners are developing, manufacturing and testing a composite liquid hydrogen tank for aerospace applications. Besides an overview of the project and the NLR activities, the focus will be on cryogenic testing capabilities and in situ liquid hydrogen testing capabilities at NLR. Within COCOLIH2T, NLR generates material properties at 20K, performs permeability tests and will test full-scale liquid hydrogen tanks in the newly developed outdoor test facility. Large amounts of liquid hydrogen are available to test containers, fuel cells and jet engines.

The presentation explores the optimization of cooling systems for electric aircraft, focusing on scalable designs for mass production. Drawing from automotive industry experiences, it emphasizes the importance of integrating tolerance requirements, space constraints and flow optimization from the outset. Special attention is given to the fluid management system, particularly the coupling mechanisms for pipes and hoses. By leveraging proven automotive strategies, transitioning from prototype to mass production is seamless, efficient and cost-effective. Henn's approach guarantees that aircraft liquid cooling systems are robust, adaptable and ready for widespread adoption.

Aircraft power demand is growing, due to the introduction of new onboard systems requiring additional power, and to aircraft size/range increase. Concurrently, concern for the impact of aviation on global warming is increasing. Thus, interest in hybrid/electric propulsion for aircraft is increasing. The introduction of this type of propulsion system introduces challenges to be faced, such as the thermal management of electrical machines. The present work focuses on the design of a novel TMS (thermal management system) for the thermal control of an advanced electric machine developed for a future much more electric aircraft.

Recently, electric motors and generators rated from 200kW to 1MW with DC voltages ranging from 500V DC to 4,000V DC have become one of the key technologies supporting the goals of hybrid electric propulsion, such as driving overall system efficiencies as high as possible while reducing system weight by increasing the power density and system simplicity. This presentation compares the advantages and disadvantages of different high voltage DC levels used in electric generators and motors and distribution equipment. Honeywell has an unparalleled generator and motor range for aerospace, based on more than 100 years of innovation and product development, ranging from hundreds of watts to 1MW.

Additive manufacturing has been revolutionary in enabling complex structural components, however, the utilization of functional materials such as soft-magnetic materials is relatively immature. 3D magnetic circuits in electrical machines have been elusive due to the high eddy current losses caused by thick cross-sections in bulk material, and the inability to process electrical steel laminations into 3D structures. By processing soft magnetic materials with additive manufacturing, geometry can be tailored to avoid thick cross-sections and reduce eddy currents whilst maintaining a 3D magnetic circuit, enabling new machine architectures that can meet the power density targets for the electrification of aviation.

Technology selection must evaluate applications and qualifying standard requirements including but not limited to electrical performance, mechanical integration and environmental use. The industry lessons learned are incremental and based on countless tests, validations and return of experiences. The novel AAM market eVTOL offers new opportunities but also many challenges we must be willing to assess, evaluate and learn from. Aviation-grade lithium-ion technologies to power the AAM EVTOL offer new opportunities but additionally many challenges. This presentation reviews a few of these challenges by comparing the latest developments and lessons learned from lithium-ion technologies.

Electrification will only make a sustainability impact for aviation if it can deliver useful mission capabilities that replace existing aircraft. VerdeGo has applied experimental data from its hybrid powerplants to model the performance of electrified aircraft with both hybrid and battery powertrains. The results of this work show a compelling case for hybridization being the propulsion architecture that will have the biggest impact on the most use cases as electrification becomes mainstream. While the automotive industry evolved from hybrids to battery power, aviation is moving in the other direction from batteries in R&D aircraft to hybrids in production use cases.

This session will explore the benefits of a battery-electric aircraft for the regional air mobility market. Attendees will gain a better understanding of how the novel propulsion technologies used by such aircraft will affect not just aircraft design, but also the airport infrastructure and operations. The session will also focus on certification and the role of regulators in achieving zero-emission targets.

Explore next-generation aerospace design and testing workflows. Understand how hardware-in-the-loop testing, using real-time cell emulation, expedites the testing and certification of your battery management system (BMS). The presentation will cover examples of automated BMS and controller testing and provide an overview of tools and methodologies that streamline the design verification phase. Delve deeper into certification and powertrain development using Simulink Real-Time and Speedgoat real-time target machines.

Presented by Matt Swift, product development lead for hydrogen heat exchangers, this segment will explore where Reaction Engines are applying their novel thermal management technologies to tackle the issues around hydrogen-fueled flight. Building on the shoulders of decades of cutting-edge development in the space sector, this expertise is now driving the next generation of green transportation, aiming to offer system-level efficiency gains while ensuring safety, reliability and repeatability. Participating in a number of funded programs, this presentation will also provide a window into those activities and outline where this funding is creating value.

Do you want to know how fuel cells can help decarbonize the aviation sector? Learn how it is possible to cover almost all of Sweden's flights with hydrogen-electric fuel cell aircraft. The world’s first commercial hydrogen-electric airplane flight utilised a PowerCell 100kW fuel cell system, marking the start of the company's journey in aviation. PowerCell Group is now a world leader in hydrogen fuel cell technology for aviation, with over 20 ongoing projects for fixed wing, e-VTOL and more, continuing the ground-breaking development of next-generation aviation fuel cells.

Fuel cell systems provide a zero-emission solution for aircraft propulsion. To assure safe and reliable fuel cell operation in aircraft, system testing has to be conducted under realistic operating conditions. Therefore the HESPTA has been developed as a flying testbed to provide a system carrier for time- and cost-effective airborne fuel cell system testing. In this keynote presentation the test platform HEPSTA will be described with the new fuel cell system generation and latest results, comprising laboratory measurements and insights on the system design, especially focusing on the concept of hybridization for power optimization and system reliability.

In the frame of the clean aviation project HyPoTraDe, NLR in the Netherlands is preparing a new test facility for ground tests of liquid hydrogen-powered fuel cell powertrains. The presentation shows the preparation of the powertrain hardware involving two 100kW fuel cells, two large batteries, electrical power distribution and five propulsor units including the innovative use of a two-phase transfer loop for collecting fuel cell waste heat for the conditioning of liquid hydrogen.

Hydrogen fuel cell technology is most cost effectively available for low-volume niche aerospace applications as an off-the-shelf system. It contains the air, hydrogen and thermal systems (balance of plant), not optimized for the application. This presentation will outline an optimized systematic approach to allow bespoke balance of plant systems to be developed for low-volume aerospace at reduced effort and cost. This can result in performance uplifts/cost reduction, such as increased power density, critical for increasing the viability of the overall fuel cell systems, helping accelerate the transition to zero-carbon fuels for niche applications.

PEM fuel cell systems play a pivotal role in realizing the aviation industry's net zero goals. Currently, PEM fuel cell systems exhibit a gravimetric power index of approximately 1kW/kg. At the system level, stacks, electric motors and humidifiers are particularly responsible for this low index. The presentation will outline the anticipated changes in system performance (efficiency, gravimetric index, aircraft resistance) compared to a baseline system. Conventional components and subsystems will be replaced with alternative variants. This will provide an estimation of how the integration of unconventional components and subsystems could enhance the performance of PEM fuel cell systems in aviation.

A plausible solution toward sustainable aviation is the use of hydrogen as an energy carrier in so-called hydrogen-electric aircraft. While these pose several technical challenges such as fuel cell or thermal management design and concept of operations, the efficacy of hydrogen storage with acceptable mass and dormancy stands out as critical enabler. This presentation introduces alternative approaches such as liquid and gaseous storage; presents key metrics such as dormancy, volumetric and gravimetric efficiency in an accessible way; and describes challenges such as impact of center of gravity as well as pressure and temperature control in liquid hydrogen tanks.

The goals to decarbonize the aerospace industries are quite formidable. When looking for ways to electrify aircraft, developing fuel cell technologies, are being looked at to provide energy to the different systems, but this will require a very aggressive R&D and validation process. This presentation will look into some of the challenges based on real examples and how they have been resolved.

The increase in urbanization and road congestion has raised the need to address new solutions for transportation. Urban Aair mobility has come up as a possible solution, supported by the advance of sustainable propulsion, energy storage systems, connectivity, automation and lightweight structures. The FLY.PT project, involving Portuguese aerospace companies, explores autonomous electric mobility combining a drone, a passenger cabin and a skateboard, for vertical and horizontal movement. The collaborative design methodology included the creation of a morphological table to support the generative phase, sketching sessions to visualize concepts and a concept selection matrix to choose and refine concepts collaboratively.

With over 300 companies delving into eVTOL aircraft development, obstacles loom large. These vehicles aren't mere electric helicopters; they're finely tuned for electrical propulsion, demanding novel approaches. Foremost among these is adopting cutting-edge technologies for safe flight. This adds to the already complex electrical systems landscape in an industry transitioning to electric aircraft. Yet, taking off is just the beginning. Meeting regulatory standards, completing flight testing and ramping up production while ensuring economic viability are essential. Traditional methods prove slow and risky in this age of digitalization. A model-based approach, leveraging digital processes is emerging as a necessity for eVTOL success.

EASA roadmap on electric/hybrid propulsion systems.

Electrohydrodynamics (EHD) came to attention in 2018 when MIT flew an aircraft propelled by ionic wind. When high voltage is applied between two electrodes, the ion discharge between the electrodes entrains air molecules creating airflow. The airflow is then directed to generate lift and thrust. Researchers have obtained thrust to power ratios of 7–100N per kW from ionic wind thrusters, comparable to light helicopters. Ionic wind propulsion could power the ultimate electric aircraft using electricity directly to create thrust. Its advantages for an eVTOL would include silent operation and elimination of rotors, with fully distributed propulsion.

In the dynamic landscape of aerospace engineering, three critical themes emerge for the success of electric and hybrid flight: axial flux motors, type certification and propulsion efficiency. This presentation delves into their interplay and implications. Axial flux motors for aerospace: these cutting-edge motors are at the forefront of aerospace innovation. By leveraging their compact design and high-power density, Evolito enhances overall propulsion efficiency. The exploration of axial flux motors promises breakthroughs in weight reduction, performance optimization, and integrated redundancy. The role of type certification in electric propulsion: as electric and hybrid propulsion systems gain prominence, understanding their certification process becomes paramount. The presentation sheds light on the pivotal role of type certification in shaping the future of electric propulsion. Regulatory compliance, safety standards and scalability are key considerations. Reshaping airframe capabilities: propulsion efficiency directly impacts airframe design. By achieving greater energy conversion and minimizing losses, engineers can reimagine aircraft mission profiles, efficiency and performance. In summary, this exploration bridges technological boundaries, emphasizing the need for collaboration between motor design, certification regulations and airframe engineers. The future of aerospace hinges on these synergies, propelling us toward more sustainable, efficient and agile flight solutions.

Explore the future of sustainable transportation beyond traditional automobiles at this presentation, where Tobias Kahnert, CEO of EFT Mobility, will delve into innovative alternatives for the aviation industry. He will uncover how cutting-edge propulsion technologies like electric, hybrid and hydrogen-powered aircraft are revolutionizing air travel while reducing environmental impact. Discover how EFT Mobility is envisioning a greener, more efficient future. Engage in discussions on the transition process and the collaborative efforts needed to propel sustainable mobility forward.

This presentation delves into advanced air mobility (AAM) route attractiveness insights, analyzing 42 global cities across six variables and three use cases. It provides a comprehensive assessment of each city's potential for AAM deployment, highlighting terrain, weather, area specifics, airspace, authority regulations and time-saving benefits. This research offers crucial insights into the future of advanced air mobility and its practical application in diverse urban landscapes.

Rapid advancement of electric vertical take-off and landing (eVTOL) and advanced air mobility (AAM) technologies presents groundbreaking opportunities for parapublic missions. This presentation explores the pivotal role of autonomy in eVTOL/AAM systems, particularly in the context of public service operations. Leveraging firsthand flight experiences, the speaker offers a unique perspective on how autonomy can transform parapublic eVTOL operations. By identifying the practical means to allow first responders, firefighters, EMS technicians and military service members to operate eVTOL aircraft safely and effectively, the presentation addresses the evolving challenges and opportunities inherent in the operation and training requirements of autonomous eVTOL aircraft.