Distributed Electric Propulsion (DEP) enables novel aero-propulsive interactions by exploiting propeller slipstream effects to modify the aerodynamic characteristics of lifting surfaces. Several numerical and wind-tunnel investigations have demonstrated the potential of distributed blowing for improving lift capability and aerodynamic efficiency in DEP aircraft configurations. However, experimental flight-test evidence at the full-aircraft scale remains limited. This work presents an experimental investigation of the trimmed aerodynamic characteristics of a DEP flying demonstrator, with specific focus on the impact of propeller-induced blowing on lift, drag, and overall aerodynamic efficiency.

The study is based on flight-test data collected during multiple automated maneuvers and processed through a dedicated identification framework that reconstructs aerodynamic coefficients from locally identified stability and control models. Trimmed lift and drag coefficients are evaluated for each maneuver and used to build CL–α, CD–α and trimmed aerodynamic polar CL–CD relationships. The dataset is clustered according to the propeller advance ratio at trim, adopted as a proxy for the intensity of distributed blowing, and second-order analytical fits are employed to highlight global trends across the explored operating conditions.

The results show a clear and consistent influence of distributed blowing on the aerodynamic characteristics of the aircraft. Increasing blowing intensity produces an upward shift and a steeper slope of the lift curve, a mild reduction in trimmed drag, and a noticeable improvement of the trimmed aerodynamic polar. These combined effects lead to a significant increase in aerodynamic efficiency over the investigated flight envelope.

Despite the inherent scatter of experimental flight data, the observed trends are robust and consistent with physical expectations and previous numerical findings. The present work provides original flight-test evidence of the aerodynamic benefits of distributed propulsion at the aircraft level and supports the potential of DEP configurations for low-speed and high-lift flight conditions.

During the design phase of a fixed-wing remotely piloted aircraft developed at Politecnico di Milano, an experimental investigation was conducted to validate preliminary sizing methods for spoileron. Traditional regression-based and semi-empirical approaches (such as DATCOM and Roskam) were compared with results obtained from a dedicated wind tunnel test campaign.

The need for validation arises from the application of these methodologies to a non-conventional configuration characterized by newly designed reflex airfoils and a distinctive geometric layout, including a highly swept wing, low aspect ratio, and pronounced taper. The lack of prior experimental data on reflex airfoils applied to similar wing configurations equipped with spoileron-type control surfaces raises uncertainties regarding the reliability of estimates derived from traditional approaches, which are generally calibrated on conventional airfoil geometries.

The wind tunnel campaign was conducted using a 1.3 m wingspan aluminum model at a Reynolds number of 1×10⁶, during which roll and yaw performance was systematically mapped by varying the spanwise and chordwise spoiler positions. In an initial phase, the ratio between spoiler chord and local wing chord was kept constant. Subsequently, the sensitivity to variations in this ratio, spoiler spanwise extension, and control surface deflection was analyzed.

Results show qualitative agreement with trends reported in the literature, highlighting maximum effectiveness at intermediate angles of attack (5–8°) and a reduction in effectiveness when the spoiler is placed toward the wing tip. Quantitatively, the measured performance is slightly higher than that predicted using traditional preliminary methods. The results therefore indicate that conventional regression-based approaches can be reasonably applied to wings equipped with reflex airfoils, despite their original calibration on conventional airfoil geometries. Moreover, the observed systematic deviation suggests the need for minor correction factors when applying these methods to similar unconventional configurations, contributing to enhanced confidence in early-stage control surface sizing.

Lighter-than-air platforms are currently gaining the attention of engineers for diverse applications. Beside their superior endurance performance granted by buoyancy as a means for countering weight, electric motors coupled to propellers, with their high thrust-to-weight ratio and small size, allow designers to deploy them within the topology of a novel airship, thus mitigating the inherent controllability issues of these platforms.

Among the missions currently envisaged for airships on Earth are high-altitude pseudo-satellite (HAPS) applications, where the ability of the airship to reposition, further increase its own flight time through solar energy harvesting, and return to base after a long-endurance flight, constitute an interesting alternative for surveillance and intelligence gathering missions traditionally associated with space satellites. Furthermore, the atmospheric and irradiance conditions encountered in the layers of the atmosphere at 18–20 km of altitude are partly similar to those found on non-terrestrial bodies. This naturally suggests an application of airships for non-terrestrial exploration especially on planets where a sufficiently dense atmosphere is present.

Lighter-than-air applications (notably, uncontrolled balloons) have already been attempted on Venus, along with preliminarily studied in the past for both Venus and Mars. However, most of the literature is less recent than the latest developments in technology, especially in solar cells and envelope material, besides that of electric motors and batteries, which nowadays can be exploited to reduce the weight and size of an unmanned airship.

This study, grounded on a pre-existing method for the preliminary sizing of airships already employed for several terrestrial applications, tries to fill this gap by analyzing the sizing solution of an airship for Martian exploration through a parameterized approach. This allows us to study the effect of different technological choices on the sizing solution, highlighting the most relevant bottlenecks towards the feasibility of this concept, dictated by constraints on geometrical dimension and mass.

Reliable characterization of atmospheric turbulence in the urban boundary layer is critical for the flight safety and structural integrity of light aerial platforms operating below 300 m. For unmanned airships, in particular, turbulence represents a well-known complication factor due to their large aerodynamic surfaces and low-speed flight regimes. An accurate understanding of near-ground conditions is essential for these vehicles, especially in Milan, where experimental activities are scheduled as part of the IPROP project. However, conventional high-resolution sensing infrastructure is often too costly or spatially sparse for real-time deployment. This study proposes a low-cost turbulence-intensity proxy, TI_b, derived from standard 10-minute ground-based meteorological data. The metric is defined as TI_b(t) = α|dU/dt|+βσ_U, capturing both impulsive shear transients and stochastic fluctuations.

The methodology was evaluated using data from two Milanese stations during April–May 2025: Lambrate (suburban) and P.zza Zavattari (dense urban core). The results show that the suburban site exhibits higher dynamic activity, with a mean TI_b of 0.142 and peak excursions exceeding 0.36, indicating frequent shear-driven bursts. Conversely, the urbancore shows a smoother environment with a mean TI_b of 0.097. This work maps these proxies to three operational risk categories—Nominal, Elevated Workload, and Caution—providing a practical heuristic for mission planning. The findings underscore the necessity of localized hazard mapping for Urban Air Mobility (UAM) and experimental airship operations in complex metropolitan airspaces.

In recent years, the utilization of space has expanded rapidly across communications and broadcasting, positioning, meteorological observation, and remote sensing, resulting in a sharply increasing demand. Under these circumstances, the number of satellites has surged, elevating the risk of collisions and raising concerns about the growing amount of space debris generated by such collisions. Satellites use liquid propellants for orbital insertion and attitude control, but they reach the end of their operational life when propellant is depleted. Many satellites remain in orbit for extended periods after the end of life, and the need to launch replacement satellites further increases the number of objects in orbit, contributing to the growth of space debris. Conversely, if on-orbit propellant refilling can be realized, it may be possible to extend satellite lifetimes and thereby suppress both the need for replacement launches and the associated increase in space debris.

The ultimate goal of the present study is to establish on-orbit propellant resupply technology, and the objective of this work is to develop in-tank gas–liquid separation techniques during propellant transfer under microgravity conditions, which constitute one of the core enabling technologies for achieving that goal. As the first step in the development of this technology, the behavior of liquid in a small, spherical mock-up tank equipped with a vane-type propellant acquisition mechanism utilizing surface tension was observed during filling with simulated propellant under short-duration microgravity conditions generated using a drop tower. Additionally, a variant of the vane-type propellant acquisition mechanism, with baffles added to the central and top sections of the support rods that install the vanes, was also fabricated and tested. It was found that the gas–liquid separation performance of the configuration with top-mounted baffles was superior to that of the other designs.

Among the most versatile lighter-than-air platforms, unmanned airships are currently being designed mostly for either low-altitude missions for close-distance surveillance, in competition with multi-copter drones, or for high-altitude missions in the stratospheric layer, thus ideally complementing the role of space satellites. Correspondingly, algorithms to automatically compute global values like the volume and mass of an airship, for a desired mission performance and for assumed technologies of the components (like the materials employed for the envelope or the construction of the gondola), have been experimented with and are already documented in the literature.

Building on this base, this research proposes a method where not just the parameters mostly typical to preliminary design are solved, but a unified automatic approach is employed for taking into account requirements on static balance as well as dynamic performance. This modular method links three original tools, developed in-house respectively for preliminary sizing, lofting and inertial modeling, and dynamic analysis. The synergistic use of the first two allows the simultaneous computation of not just the weight and volume of the machine for a specific mission, but also a detailed static balance problem, by suitably arranging the masses of the components onboard. The last module further tweaks the positioning of selected components to obtain better flying qualities. The latter are measured by means of damping and the characteristic time of specific eigenmodes of the system, in turn obtained after drawing a linearized model of airship dynamics from a fully non-linear one.

The outcome of the overall unified sizing procedure, numerically configured as an automatically solved optimal problem, accounts not just for the requirements of the mission profile, but also potentially for static balance and for a desired level of flying qualities. The full procedure is demonstrated on the data of an existing small-scale airship prototype.

During flight, helicopter rotor blades generate significant vibrations and noise due to aerodynamic loads. These effects limit maximum flight speed, increase operating costs, and reduce the fatigue life of structural members. The use of active control systems for helicopter rotor blades is a current scientific trend of research into noise and vibration reduction. Several methods exist for actively controlling helicopter rotor blades. One control strategy applied to suppress vibrations is Higher Harmonic Control (HHC) and Individual Blade Control (IBC). Currently, several methods of helicopter blade control are being researched with the development of piezoelectric fibres: Active Trailing Edge (ATE) and Active Twist (AT).

Active Twist is based on the fact that the actuator control elements can be located on the blade's load-bearing skin surface. The orientation of the piezoelectric fibres in the piezoelectric actuator on the top and bottom surfaces of the skin is ±45°, resulting in dynamic blade twisting when the piezoelectric actuators are activated. Thus, Active Twist can be integrated into the existing rotor blades without significant design changes.

In the present work, an analysis of a numerical study of a helicopter blade with the piezoelectric actuators integrated into the skin of the main rotor blade was performed. The results of static blade twisting as a function of the piezoelectric actuator chord-wise length are presented. Additionally, the effect of changing the geometry of the blade's cross-section on the twist angle was examined. The influence of piezoelectric actuators and changing the geometry of the blade's cross-section on the stiffness characteristics of the helicopter blade are demonstrated.

Additive manufacturing (AM), defined as a layer-by-layer fabrication process driven by digital design data, enables the realisation of geometrically complex structures that are unattainable through conventional subtractive or formative methods. By allowing material placement only where structurally necessary, AM provides unprecedented control over internal architecture, mass distribution, and functional integration. Lightweight structural design is a critical requirement for modern aerospace systems, particularly for unmanned aerial vehicles (UAVs) and small-scale platforms where mass directly governs endurance, payload capacity, and operational efficiency. Topology optimisation combined with additive manufacturing offers a promising route to overcome the inherent limitations of polymer materials by enabling highly efficient internal material architectures.

This study investigates the experimental performance of topology-optimised lattice structures manufactured using fused deposition modelling (FDM) for lightweight aerospace applications. A function representation (F-rep)-based parametric design framework was developed to generate cylindrical lattice architectures with controlled lattice frequency and vertical phase shift. Seventy-eight (78) specimens were fabricated from polylactic acid (PLA) across three infill regimes (30%, 70%, and 100%) and tested under quasi-static axial compression in accordance with ASTM 1621-16. Mechanical performance was evaluated in terms of maximum compressive load and strength-to-mass ratio.

The results show that topology-optimised lattice structures significantly outperform solid reference specimens in mass-specific mechanical performance. The greatest enhancement was observed at 70% infill, where lattice structures achieved improvements in strength-to-mass ratio of up to 68.42% compared to solid specimens. Lattice architectures also exhibited progressive collapse behaviour, indicating improved damage tolerance.

These findings demonstrate that topology-optimised, additively manufactured polymer lattice structures provide a viable and scalable pathway for developing lightweight, structurally efficient aerospace components, particularly for UAV and small-platform applications.

The EU EFACA project considers two conceptual aircraft design configurations for cleaning European air traffic in future decades. The EU SENECA project considered four conceptual configurations for supersonic aircraft design—it is also expected to impact air traffic in future decades. Recently, several different technologies have led to propulsion designs that have the potential to reduce greenhouse gas emissions and replace existing conventions, including jet fuel technology. On one hand, H₂-powered aviation just recently regained significant attention from the industry, e.g., Airbus launched the ZEROe program, where they pledged to develop the world’s first zero-emission commercial aircraft by 2035. On the other hand, sustainable aviation fuels or biofuels have been identified as an alternative option, also with the potential for use in supersonic flights. In both projects, the results of the assessment of environmental factors are considered using a multidimensional approach, ranging from aircraft certification requirements to regional/global assessment of new designs in air traffic. Any factor reduction technology is simulated and compared to a reference, usually the current best in its aircraft class, providing the possibility to assess its efficiency for necessary certification requirements and for real or forecasted operational conditions, in particular due to the ACARE goals assessment in mid-2035 and long-term 2050 terms.

The increasing proliferation of space debris poses a significant and growing threat to operational spacecraft and future space missions. Our research aims to address the growing concern about space debris and the need for accurate trajectory predictions to ensure the safety and sustainability of space operations. Our approach combines machine learning for space object classification with classical filtering techniques for trajectory prediction, resulting in an interactive visualization of the spatial environment. The initial phase of our research consisted of applying a Random Forest Classifier for the accurate detection and classification of space objects, distinguishing between active satellites and space debris. Subsequently, our research used a Kalman filter to predict the trajectories of both active satellites and space debris. This allowed us to obtain dynamic and precise position informations for these space objects. Finally, a 3D visualization has been developed to illustrate the behavior and movement of both debris and active satellites. Preliminary results, obtained by extracting orbital parameters such as semi-major axis, inclination, right ascension of the ascending node (RAAN), argument of perigee, and mean anomaly from Two-line element (TLE) data, indicated a good classification accuracy of approximatively 98% for distinguishing between different types of space objects during the training phase.