The aircraft cabin and boarding procedures are steadily increasing focus points for both aircraft manufacturers and airlines, as they play a key part in the customer experience. In the German research project AVACON (AdVAnced Aircraft CONcepts), the boarding procedure is assessed using the PAXelerate boarding simulation. As the project demands an increased level of detail concerning the passenger movement model, this publication introduces an improved methodology. Additions to the model include the development of a method capable of describing the passenger walking speed in dependence of the surrounding objects, their proximity as well as the location of other passengers within the cabin. The validation of the model is performed using the AVACON research baseline and an Airbus A320. The model is then applied to an altered version of the Airbus A320 with an extended aisle and to a COVID-19 safe distance scenario. Regarding the results, an extended aisle width delivers boarding times reduced by up to 3%, whereas the COVID-19 assessment delivers a 67% increase in boarding times. Concluding, the integration of the newly developed model empowers PAXelerate to simulate a more detailed boarding process and enables a better understanding of the influence of cabin layout changes to an aircraft’s boarding performance.

The air transport system faces pressing challenges arising from CO2-emission reduction targets, fragmented passenger needs, and a highly competitive market environment. Aiming for a reduction of CO2-emissions in the long-haul sector, a holistic solution is suggested incorporating both operational and technological innovations in three areas: (1) changes in the air transport network structure, (2) (liquid) hydrogen as energy carrier, and (3) new aircraft and cabin design. To these ends, this paper focuses on the implications resulting from a passenger-distance improved air transport network. Demand pooling is proposed to enable higher load factors, offer more point-to-point connections for passengers, and generate new revenue sources for airlines. Based on a discussion of traditional airline business models, a seat exchange platform named “ShAirline” is proposed, allowing multiple providers to rent out cabin space. The underlying business model is evaluated considering implications for aircraft and cabin design, new passenger services, additional revenue opportunities, passenger journey times, required aircraft, as well as implications for airports. Findings indicate that the proposed seat exchange platform in conjunction with a change in aircraft ownership structure assist in removing inefficiencies across the current long-haul network and help offset barriers connected to the use of novel eco-efficient technologies.

This paper presents an integrated assessment of liquid hydrogen as an aviation energy carrier, covering fuel production, aircraft performance, and fleet-level climate impacts. The results, based on the H2Avia research project, indicate substantial potential for reducing life-cycle global warming impacts compared to conventional kerosene. The analyses conducted for the interdisciplinary assessment are presented. The analysis shows that the use of liquid hydrogen eliminates CO₂ emissions during fuel burn, resulting in a significant reduction in global warming potential compared to conventional kerosene, despite remaining upstream emissions from production and transport. The aircraft application cases and the applied technologies assessment scenario are described. The modeled technologies essential for the hydrogen aircraft are discussed, and exemplary values are given. Integrated overall aircraft performance results are given and discussed. At the aircraft level, hydrogen-based aircraft require an 8–18% increase in design mission block energy compared to a 2040 kerosene baseline yet still achieve a reduction in effective global warming potential of 55–86% comparing a representative pair route between Europe and North America (6730 km). An overview of the fleet modeling approach and the applied scenarios is given. For a scenario with energy cost and climate impact as equally weighted minimization goals, the global fleet analysis yields a global warming potential reduction of 60% compared to the non-liquid hydrogen baseline scenario. Overall, the results suggest that liquid hydrogen-powered aircraft can deliver significant mission- and fleet-level reductions in global warming potential and thus represent a promising pathway for achieving long-term aviation climate targets.

Liquid hydrogen (LH₂) has been identified as a potential solution to the ever-growing climate impact of the aviation sector. One of the key problems for the industry remains the provision of the necessary storage volume, which results from the low density of hydrogen. The objective of this paper is to quantify the potential for structurally integrated conformal wing tanks for liquid hydrogen. The three wing tanks derived for the CHoSe project contain internal rib structures and are placed inside the center wingbox as well as from wing root to kink. The multidisciplinary aircraft design environment BLADE has been extended by the capabilities to complement liquid hydrogen fuselage tanks with wing tanks of varying area mass. Comparing short-to-medium range (SMR) aircraft with only fuselage tanks and with additional wing tanks resulted in key findings: for similar area mass assumptions for fuselage and wing tanks of 20 kg/m², no fuel burn benefit could be achieved. The decrease in fuselage length could not compensate for the increased structural tank masses. No significant load alleviation effect on the wing structure can be expected due to the limited mass and lever arm of the tanks inside the wing. Small efficiency gains can only be expected when synergistic stiffening effects with the load-carrying structure of the wings reduce the effective added area mass to lower values than for the fuselage tanks. Adding tanks further outbound than the wing kink deteriorates the performance, even for the most optimistic tank assumptions.