Improving fuel efficiency is a primary challenge in modern aviation, with aerodynamics serving as a key enabler. Aerodynamic friction drag accounts for more than 50% of total drag, highlighting a significant opportunity for efficiency gains through laminar flow, which reduces skin friction drag. In addition, increasing the wing aspect ratio while maintaining a constant lift coefficient to achieve maximum lift-to-drag ratio can further improve aerodynamic performance. However, evaluating laminar flow in isolation, without considering overall mass, system power requirements, or engine performance, can lead to an incomplete assessment of its true technological potential. In this study, a conceptual design methodology was applied to integrate laminar-flow technologies (natural and hybrid) across the wing, empennage, nacelle, and fuselage of a 2035 long-haul reference aircraft. Results indicate a potential for 16% block fuel reduction at the aircraft level, with wing aspect-ratio tailoring delivering up to 24% fuel savings. These findings will be refined through detailed disciplinary analyses in future work.

The aviation industry is under increasing pressure to enhance sustainability by improving energy efficiency and reducing climate impact. A promising approach is to reduce aerodynamic drag using laminar flow technologies, particularly Natural Laminar Flow (NLF) and Hybrid Laminar Flow Control (HLFC). Previous research has primarily focused on aerodynamic performance, often considering only one technology at a time, using simplified HLFC system design models, and targeting long-range aircraft. This study adopts a more holistic approach by conducting a conceptual design of a short-medium range (SMR) aircraft equipped with both NLF and HLFC. The technologies are applied to the wing and empennage, with detailed HLFC system modelling integrated into the conceptual design process using established methods. A failure analysis is also performed to assess the performance impact of potential malfunctions. Results indicate that combining NLF and HLFC can reduce fuel consumption by 5.9% on the design mission compared to a fully turbulent reference aircraft. Moreover, selectively applying the technologies to specific components enhances fuel savings while reducing system complexity. These findings demonstrate the potential of laminar flow technologies to improve fuel efficiency in SMR aircraft and highlight the importance of integrated aerodynamic and systems-level evaluation.