Hybrid-Electric Regional FUSelage & Empennages

Project Information

HERFUSE

Grant agreement ID: 101140567

DOI

10.3030/101140567

EC signature date 12 December 2023

Start date 1 January 2024

End date 31 December 2026

Funded under

• Climate, Energy and Mobility

Total cost

€ 32 989 854,98

EU contribution

€ 25 726 931,51

Coordinated by

LEONARDO - SOCIETA PER AZIONI
Italy

Periodic Reporting for period 2 - HERFUSE (Hybrid-Electric Regional FUSelage & Empennages)

Reporting period: 2024-10-01 to 2025-09-30

Summary of the context and overall objectives of the project

HERFUSE (Hybrid-Electric Regional FUSelage & Empennages) aims to design innovative fuselage and empennages for future Hybrid-Electric Regional aircraft (HER) to reduce Green House Gases (GHG) emissions.
It addresses challenges in layout, materials, components, manufacturing, and assembly, integrating features for hybrid-electric propulsion and complementary systems to improve weight, durability, aerodynamics, and operations.
The project aligns with the HERA project, focusing on regional aircraft, and aims to achieve performance gains through technologies such as low GHG energy sources, storage, distribution, operational features, and thermal management. HERFUSE's technical solutions will contribute to reducing emissions at the aircraft level, in tandem with HERA's objectives.

With the intent to support as much as possible the final objectives of Clean Aviation Phase 2, the project team is resteering the project with a re-modulation of regional aircraft integration efforts in Clean Aviation for an optimal use of resources.
HERFUSE has received CAJU request to revise fuselage and empennage to support flying demonstrator by 2030 and an aircraft configuration EIS 2035. HERFUSE goal is now to include new technologies, technical design solutions, manufacturing and assembly solutions matching HERA and future Ultra Efficient Regional Aircraft.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

During the second reporting period, the following work has been done:
On the management side, the amendment has been officially submitted by Leonardo in August 2025 and formally approved by CAJU in October 2025. The amendment incorporates the workscope remodulation towards the UERA configuration, the inclusion of ATR as Leonardo’s affiliated entity and APPLUS as newcomer on UCB demonstration activities.
Moreover, following the last review recommendations, collaboration with EASA has officially been resumed with LDO as technical coordinator of the activities, and with the scheduling of two technical familiarisation meetings with EASA both on UERA use case and UCB. Additionally, a good progress on this topic has also been shown at the last Regional Thrust at EASA premises in Koln.
On the technical standpoint, Conceptual Design activities have been closed on UCB, solving the issue of Hydrogen tank allocation and defining a space allocation model for all hybrid electric propulsion systems related to fuel cell propulsion, and almost finalized on UERA where the fuselage and the vertical empennage (VE) concepts are available and horizontal empennage is in progress. Moreover, trade off studies have been performed on UERA first configuration (released by HERA with D5.27 R01) and considering different solutions. After the trade-off, the hybrid solution emerged as the optimal choice although it would present issues in reaching block fuel savings on aerodynamics (ref. SRIA 2 objectives) raising the need to find a new solution to avoid battery storage into the karman. Trade off evaluations brought HERA and HERFUSE teams working jointly to release a new configuration enabling the batteries’ storage into the underfloor area. The new UERA configuration has now a circular cross section underfloor modified to allocate the batteries compartment.
On the technologies standpoint, tests strategies for both use cases show a good progress as detailly explained into the dedicated session of this report and results are now being used to progress with tests at component level in WP6 with a focus on the technologies used for the VE demonstrator in UERA and fuselage panels in UCB. A dedicated presentation has also been prepared to support the validation of the new milestone “Technologies’ final assessment” M4.1-2.
On design activities, preliminary and stressed design are in progress for both use cases fuselages and empennages being loads now available and stress analysis has also been performed for all intermediate demonstrators of UERA use case.
On demonstrators’ schedule, the test plan and manufacturing instructions have been defined for the UERA VE and the fabrication of VE main items has been started (skin stringer panels in progress). UCB shows very good progress as well with the realization of liquid resin infusion panel and progressing on other panels of central fuselage.
Life cycle assessment tasks are in progress for both use cases with the creation of a parametric model open to include new parts, allowing it to follow the design evolution of the concepts through the design activities. Additionally, a preliminary version of the SimaPro model has been created and the map of the innovative technologies and processes proposed by industrial partners for the fuselage and empennage of both use cases has been finalized, and the related product tree has been defined. The development of the bill of materials describing all the affected components suitable to concur to the environmental impacts is in progress.
Activities on certification and compliance verification show very good progress with the involvement of EASA.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The completion of the Conceptual Design represents a key milestone in the project compared to the current state of the art.
The hybrid aircraft architecture has been defined for both use cases, including the placement of batteries and fuel cells in the fuselage, along with the related thermal management and electrical distribution systems.
Regarding structural technologies, a significant step forward compared to the state of the art has also been made with the design of the vertical empennage in a bonded configuration and the release of the PDR for the fuselage panels of Case B.
Regarding certification, periodic meetings with EASA have led to the identification of risks associated with new structural technologies and the initiation of the means of compliance identification process.

Liquid Resin Infusion panel of UCB

UERA Vertical Empennage DEMO skin stringer panel

UERA Fuselage with systems allocation

UCB Fuselage with systems allocation