A concise overview of the overall layout of an experimental powered high-speed flight vehicle including its subsystems is given. A mission scenario, the different flight segments and events to which the payload is exposed are described and justified. This allowed the definition of the aero-thermo-mechanical loads required to conceptually design all elements on board of the vehicle. The final vehicle configuration could achieve the different mission objectives. In particular an aero-propulsive balance, i.e. thrust ≥ drag and lift ≥ weight, could be established at a cruise Mach number of M = 7.4 on the basis of a hydrogen powered scramjet engine while guaranteeing a good aerodynamic efficiency L/D ≥ 4 in a stable, trimmed and controlled way. The experimental combustion campaign could last for at least for 3s up to 9s pending on the finally obtained flight level. This test time is very valuable as it is about 3 orders of magnitude higher of what can be tested in European ground facilities. The vehicle made maximum use of databases, expertise, technologies and materials elaborated in previously EC co-funded projects ATLLAS I & II and LAPCAT I & II.Based on this conceptual design, the consortium has arrived at a key point where they feel comfortable to go to the next step in establishing a detailed design of the vehicle and the preparation of the launch vehicle and flight campaign.

Achieving airbreathing hypersonic flight is an ongoing challenge with the potential to cut air travel time and provide cheaper access to space. Waveriders are potential candidates for achieving hypersonic cruise or acceleration flight within the atmosphere. Current research tends to focus on key issues like thermal loading, aero-elasticity and aerothermodynamics at hypersonic speeds. Design problems in each of these areas must be solved if a hypersonic waverider design is to be viable.

This paper deals with the design trade-off activities undertaken to provide a trim-able, a statically and dynamically stable vehicle configuration able to perform a nominal experimental scramjet-propelled flight. The flight control activities and their impacts on vehicle layout and global aerodynamic performance are also addressed. In particular, different competing aeroshapes have been investigated to assess the best one camplyant with project requirements. In this framework, trade-off results in terms of: setup and/or analysis of aero-propulsive databases; design loops for the aileron (shape, span, length); design loops for the vertical tail (shape, size, toe-angle); analysis of aerodynamic performances; analysis of longitudinal trimming conditions; sensitivity to centre of gravity position of static longitudinal stability and trimming conditions; static stability analysis (for longitudinal and lateral-directional flight) in clean and flapped configuration, static margins (pitch, roll, yaw); dynamic stability analysis with a focus on roll-yaw coupling (linearized model analysis and Dutch-Roll period evaluation); characterization of hinge-moments; and preliminary selection of flight control equipment are provided and described in detail in the paper. Nomenclatureaerodynamic drag, diameter E = lift-to-drag ratio (aerodynamic efficiency) H, h = altitude, height L = length, aerodynamic lift M = Mach number, moment 1 Ph. D.2 M = mass P = pressure p, q, r = angular rates (roll, pitch, yaw) R = gas constant S = surface T = temperature, torque u, v, w = velocity components V = velocity, volume W = width X,Y,Z = coordinates Greek Symbols  = angle of attack  = angle of sideslip Δ = variation δ = aileron deflection ε = emissivity coefficient φ = roll angle ω = angular speed τ = shear stress

This article proposes a novel approach to the Distributed State Estimation (DSE) problem for a set of co-operating UAVs equipped with heterogeneous on board sensors capable of exploiting certain characteristics typical of the UAS Traffic Management (UTM) context, such as high traffic density and the presence of limited range, Vehicle-to-Vehicle communication devices. The proposed algorithm is based on a scalable decentralized Kalman Filter derived from the Internodal Transformation Theory enhanced on the basis of the Consensus Theory. The general benefit of the proposed algorithm consists of, on the one hand, reducing the estimation problem to smaller local sub-problems, through a self-organization process of the local estimating nodes in response to the time varying communication topology; and on the other hand, of exploiting measures carried out nearby in order to improve the accuracy of the local estimates. In the UTM context, this enables each vehicle to estimate both its own position and velocity, as well as those of the neighboring vehicles, using both on board measurements and information transmitted by neighboring vehicles. A numerical simulation in a simplified UTM scenario is presented, in order to illustrate the salient aspects of the proposed algorithm.

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