NACRE novel aircraft concepts

Abstract

Commercial transport aircraft developed today are defined to balance all requirements foreseen for the short or medium term. Best engineering knowledge as much as minimum business risks consistently lead to the so-called ‘classic’ aircraft configuration. This balanced approach is efficient but can also inhibit innovative practices. Ensuring a sustainable growth in the aviation sector may require radical changes in the way we design and operate aircraft. Started in April 2005, NACRE is a four-year European research and technology integrated project, partly funded by the European Community under the Sixth Framework Programme, which aims at integrating and validating technologies that will enable the potential of new aircraft concepts to be assessed. In order to explore the most relevant capabilities and meet the widest range of challenges, the NACRE R&T project has identified a set of concepts tailored to address specific subsets of design drivers: • The Pro-Green aircraft concepts putting a major emphasis on the reduction of environmental impact of air travel; • The Passenger-driven Aircraft concepts aiming at optimised payload and appreciable quality of future aircraft for the end users; • The Simple Flying Bus, which puts the biggest emphasis on low manufacturing costs and minimum cost of ownership. Irrespective of what final future product configurations might ever look like, the NACRE aircraft concepts act as basic vectors, encompassing all the expected capability developments. The general project objectives are thus to use these concepts in order to: • Explore alternative routes for the major aircraft components (fuselage, wing, engine integration) better suited to their specific targets and which would have been rejected in a balanced approach; • Provide better answers to the full range of requirements by developing and, in some cases, validating the associated envelope of innovative component designs and associated technologies. NACRE is by essence a focused multidisciplinary approach. It does not concentrate on one specific aircraft concept, but it is aimed at developing solutions at a generic aircraft component level, which will enable the results to be applicable for a range of new aircraft concepts. For each of the major aircraft components, the multidisciplinary investigations will require an exploration of the different associated aspects of aerodynamics, materials, structure, engines and systems with the goal of setting the standards in future aircraft design, thus ensuring improved quality and affordability, whilst meeting the strengthening environmental constraints (emissions and noise), with a vision towards improving significantly the global efficiency of the air transport system.

A model for aircraft evaluation to support strategic decisions

“…in order to reduce the negative environmental impact of the aviation industry (Dray, 2013;Frota, 2010;Haddad & Fawaz, 2013;Dray,2013).…”

Preliminary design of a short-medium range windowless aircraft

“…The increase in air traffic is expected to grow with an annual trend of 4.3%, in the next 20 years, in accordance with the Airbus Global Market Forecast 2019-2038; 1 thus, there is a greater focus on the environmental impact generated by the transport sector. In this perspective, much research is aimed at defining and developing new designs and technologies to reduce fuel consumption and, consequently, of polluting emissions.…”

Emissions and Aviation: Towards Greener Air Transport

“…BWB aircraft have a flattened and aerofoil shaped fuselage, which produces lift along with the wings. Different BWB concepts have recently been studied by the Royal Aeronautical Society's Greener-by-Design initiative (Green, 2002), the MIT-Cambridge University Silent Aircraft Initiative (Dowling, 2007), the European NACRE (New Aircraft Concepts REsearch) project (Frota et al, 2011), the Boeing SUGAR program (Bradley & Droney, 2011), MIT (Greitzer et al, 2011), and a further Boeing study commissioned by NASA's 'Environmentally Responsible Aviation' (ERA) project (Bonet, 2012) (Fig. 13.3).…”

“…These are typically conventional tube-and-wing designs, but incorporate significant changes to existing types. One of the most common is tail-mounted engines for noise shielding, such as designs by NACRE (Frota et al, 2011), the Conceptual Research Corporation (CRC) (Raymer et al, 2011), and TOSCA (Vera Morales et al, 2011). One of the most commonly proposed engines for this configuration is the 'open rotor' (or 'unducted fan').…”