September 24, 2019


ESTRO establishes a set of objectives that lead to a set of challenging results, which will have an impact at several levels, namely by:

The aim of ESTRO is to improve the performance of regional aircraft by integrating and validating advanced technologies for laminar flow robustness and load control effectiveness. At this end, ESTRO will define an experimental and theoretical assessment of laminar flow robustness, aerodynamic performances and load control effectiveness for a turboprop A/C wing. The experimental campaign will perform wind-tunnel tests on an already available flexible wing half- model equipped with innovative morphing active devices. The theoretical analysis will have the objective to extend wind tunnel test results to actual flight conditions.

  1. Aircraft Design. The outcome will be used in successive projects to improve the designing and sizing process of the next regional aircraft generation and the integration of advanced technologies such as laminar flow and load control. These tools could be easily extended to other aircraft categories, such as general aviation and commercial aircraft.
  2. Aerodynamic Performance. The correct prediction of the extension of laminar flow in presence of morphing active devices on the wing will contribute to improve the general aircraft sizing process, with benefits on the final aircraft noise and emission. ESTRO will therefore support a theoretical activity including the development of methods and tools to evaluate laminar flow robustness in actual flight conditions, resulting in a positive ecological impact.
  3. Improving the European industry competitiveness. The development of new tools for the correct evaluation of robustness of laminar flow will allow the design of more efficient aircrafts helping in the fulfilment of the ACARE goals, which are fundamental for all H2020 projects and will support the competitiveness of the European aeronautic industry.
  4. Addressing two of the societal challenges established at the European level, namely the “Smart, Green and Integrated Transport”, mainly through the contribution towards more efficient aircrafts, and “Climate action, Environment, Resource Efficiency and Raw Materials”, mainly through the use of more efficient and advanced systems for load control effectiveness.

The regional aircraft market continues to be a key growth sector within commercial aviation, contributing significantly to efficiencies in the airline networks and ensuring safe and seamless mobility, while respecting environmental obligations.
The integration of innovative and affordable technologies in future aircraft platforms is a key success factor for manufacturers as it increases the appeal and customer benefits, providing a better inflight experience for passengers. Furthermore, airlines derive significant economic advantages from operating modern aircraft which are more efficient, eco-friendly, easier and cost-efficient to manage and maintain, saving money through the reduction of operating costs.

New and improved technologies positively impact all these elements, contributing to a reduction in operating costs through lower fuel burn, reduced maintenance costs, reduced navigation and airport fees as a result of structural weight savings due to innovative aircraft configurations and the use of lighter materials. All these benefits and economic advantages will be even more evident for regional turboprop aircraft that are typically less expensive to operate than regional jets. Technological enhancements also appeal to passengers who can enjoy a better inflight experience thanks to improved comfort and lower cabin noise levels, and this means less noise in and around airports too. Regional aircraft typically operates over airports located in the neighbourhood of densely populated areas, with high frequency of take-off / landing events and, hence, they strongly contribute to community noise and gaseous emissions. These issues currently limit further growth of traffic operated by regional airliners which, in the next future, will have to face even more stringent environmental constraints worldwide as prescribed by civil aviation certification normative. Therefore, in accordance with Flight Path 2050 toward a drastic reduction of air transport environmental impact over next decades, several mainstream technologies have been considered in the frame of Clean Sky II– Regional Aircraft program for application to next-generation regional aircraft. Such technologies are concerning: i) advanced aerodynamics and load control to maximise lift-to-drag ratio in both design and off-design conditions of the whole flight mission profile, thus reducing fuel consumption/ air pollutant emission and also allowing for steeper/ noise-abatement initial climb paths; ii) load alleviation to avoid loads from gust encounter and manoeuvre exceeding given limits, thus optimising the wing structural design for weight saving; iii) low airframe noise to reduce aircraft acoustic impact in approach/ landing flight configurations. Natural Laminar Flow (NLF) has been recognized as one of the key green technologies which may lead to significant improvement in the aircraft aerodynamic performance by reducing skin friction drag in cruise conditions, with consequent reduction of fuel consumption and, hence, of environmental pollutants emission. In this scenario, the activities planned in ESTRO will find their implementation in the future Regional Turboprop aircraft. The magnitude of the expected impact is related to the envisaged, but realistic, advantages to improve the aerodynamic performances of a regional turboprop aircraft concept, featuring a seating capacity ranging from 20 to 130 seats, 3000 nm range / cruise Mach 0.74 / 35,000 ft flight level. ESTRO will contribute by providing support to CS2- REGIONAL domain driven by Leonardo Aircraft by performing the experimental wind tunnel test campaign, at low and high Mach numbers, of the elastic NLF wing of the TP90 A/C equipped of morphing devices for high lift and load control and by predicting numerically the aerodynamic and laminar flow performance at flight Reynolds numbers. The outcome will provide results and knowledge for future comparison with other projects involving wind tunnel experiments, flight tests and computational results. This will help improving the procedure for the design of smart wings of the next generation of turboprop aircraft by better predicting laminar flow performance, LC&A effectiveness, loads and hinge moments of control surfaces in transonic conditions (before flight tests) and aerodynamics characteristics.

In a larger scope, the expected impact of ESTRO lies within three major areas:

  • Society and Environment;
  • A larger impact on innovation and knowledge integration;
  • Transverse application to different sectors.