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The present paper aims to assess the reliability and the limitations of analysing flight stability of a box-wing aircraft configuration known as PrandtlPlane by means of methods conceived for conventional aircraft and well known in the literature.

Results obtained by applying vortex lattice methods to PrandtlPlane configuration, validated previously with wind tunnel tests, are compared to the output of a “Roskam-like” method, here defined to model the PrandtlPlane features.

The comparisons have shown that the “Roskam-like” model gives accurate predictions for both the longitudinal stability margin and dihedral effect, whereas the directional stability is always overestimated.

The method here proposed and related achievements are valid only for subsonic conditions. The poor reliability related to lateral-directional derivatives estimations may be improved implementing different models known from the literature.

The possibility of applying a faster method as the “Roskam-like” one here presented has two main implications: it allows to implement faster analyses in the conceptual and preliminary design of PrandtlPlane, providing also a tool for the definition of the design space in case of optimization approaches and it allows to implement a scaling procedure, to study families of PrandtlPlanes or different aircraft categories.

This paper is part of the activities carried out during the PARSIFAL project, which aims to demonstrate that the introduction of PrandtlPlane as air transport mean can fuel consumption and noise impact, providing a sustainable answer to the growing air passenger demand envisaged for the next decades.

The originality of this paper lies in the attempt of adopting analysis method conceived for conventional airplanes for the analysis of a novel configuration. The value of the work is represented by the knowledge concerning experimental results and design methods on the PrandtlPlane configuration, here made available to define a new analysis tool.

The paper aims to detail the educational flight testing activities performed at the Department of Aerospace Science and Technology at the Politecnico di Milano (DSTA-PoliMi), including the development of low-cost, reliable flight testing instrumentation (FTI) and the administration of the graduate course in flight testing.

The flight testing course program closely adheres to the typical content of an introductory course offered in a professional flight testing school. However, within academic courses, it has a unique feature: each student is required to plan, perform and report on a real flight test experience, acting as a flight test engineer. Educational activities in this framework have been successfully matched to applied research and technical support for private companies.

At the educational level, several elements arise that are rarely concentrated within a single course, such as multidisciplinary integration, individual conceive-design-implement-operate (CDIO) project, real-life experimental procedures and techniques, teamwork, communication and reporting, relation with non-academic partners.

Based on the development of a FTI system for light aviation and on the flight testing course, DSTA-PoliMi has built a solid capability in flight testing, introducing graduate students to this specific niche of expertise and empowering co-operation with companies in the light aviation environment, while offering capabilities and tools that are typically regarded as a prerogative of major aerospace companies.

The paper discusses an original approach to flight testing education in an academic setting that avoids the high costs and complexity connected to certified aircraft flight operations and instrumentation, nevertheless allowing the achievement of significant results, also in applied engineering research.

The purpose of this paper is to outline a novel concept of radio altimeter CRW-13 that has been designed and developed in the Lukasiewicz Research Network – Institute of Aviation as a result of the need to update the outdated structure of RWL-750M.

The new design of the device consists of integral antennas and signal processor for smart digital signal filtering.

As a result of a number of laboratory tests and flight tests of the device installed on MP-02 “Czajka” ultralight aircraft promising results were achieved. They allow to move on to the next stage of implementation and preparation for the device certification.

The CRW-13 meets with great interest of civilian and military potential customers. It is an ideal solution for airplanes, helicopters, unmanned and guided missiles. The universal design enables installation on many different platforms where exact height measurement is needed and crucial.

At the origin of the new concept was the need to replace the separate transmitting and receiving antennas with one unit comprising two planar microstrip antennas placed directly next to each other on a common plate block in the transceiver. This solution eliminates thick antenna cables and coaxial connectors, which are the most unreliable and problematic elements of radio altimeters. The new concept of integral antennas and the use of signal processors for smart digital signal filtration made it possible to take the technology to the next level.

The purpose of this paper is to present a definition of modern configuration for a medium-altitude long-endurance unmanned aerial vehicle (MALE UAV) and its on-board systems to obtain a suitable basis for future definitions such as a possible logistic support configuration first hypothesis.

Starting from high-level requirements, both the UAV conceptual design and on-board systems preliminary design have been carried out through proprietary tools. Then, some peculiarities from previous studies, such as systems advanced UAV alternative energy, have been maintained and confirmed (diesel propulsion and energy storage system).

The improvement of a component of an aircraft can play a relevant role in the whole system. In the paper, it is considered how a concept of MALE UAV can evolve (this topic is considered by the authors since many years) by incorporating advanced on-board systems concepts.

The numerical results promote and support the use of advanced on-board system solutions and architectures to improve the effectiveness, efficiency and performance of MALE UAVs.

Usually, conceptual and preliminary design phases analyze in-depth the aerodynamic and structural solutions and aircraft performance. In this study, the authors aim to focus on the advanced on-board systems for MALE UAVs. This kind of aircraft is not yet a mature concept, with very few operating machines and many projects in the development phase.

“Safety is no accident.” It is not a coincidence that this slogan appears often in FAA literature, correspondence and advisory circulars. It is a frequent reminder to all of us that reliability and safety in aviation is a team effort and that all individuals are responsible for doing their part towards the maintenance of a safe flying environment. Presents aviation safety in the TQM framework of customer focus, continuous process improvement and total involvement. Identifies customers at various levels and illustrates, with examples, how continuous improvement occurs. Highlights the mechanism in place which helps ensure these improvements. Shows that total involvement yields safety, reliability and quality in the aviation services that we receive today. Discusses the presence and prevalence of TQM in various sectors of aviation and suggests that further continual improvements are still needed in today’s aviation.

This paper aims to describe the idea behind and design of a miniaturized distributed measurement system based on a controller area network (CAN) data bus.

The intention of the designers was to build a light and modular measurement system which can be used in remotely piloted aircraft systems and ultra-light aircraft during flight tests, as well as normal operation. The structure of this distributed measurement system is based on a CAN data bus. The CAN aerospace standard has been applied to the software as well as the hardware comprising this system. PRP-W2 software designed for PCs is an additional component of the proposed measurement system. This software supports data acquisition from a recorder unit and allows for preliminary data analysis, as well as data conversion and presentation.

The system, complete with a high-speed data recorder, was successfully installed on board of an MP-02 Czajka aircraft. A research experiment using the system and oriented on airframe high frequency vibration analysis is presented in the final part of this paper.

This measurement system allows analysis of high-frequency vibrations occurring at selected points of the aircraft. A data set is recorded by three-axis accelerometers and gyroscopes at frequencies up to 1 kHz.

The use of a miniature and lightweight modular measurement system will, in many cases, be faster and less expensive than full-scale measurement and data acquisition systems, which often require a lengthy assembly process. The implementation of this class of lightweight flight test systems has many advantages, in particular to the operation of small aircraft. Such solutions are likely to become increasingly common in unmanned aerial vehicles and in other light aircraft in the future.

The adaptation of a distributed measuring system with a high frequency of measurements for purposes of small and miniature aircraft.

Attitude and heading are very important measurements on board aircraft. In modern solutions they are measured by the attitude and heading reference system (AHRS). In some small unmanned systems, the GPS track angle is used for heading corrections instead of the magnetometer; then, the system measures the track angle instead of heading. With a temporary lack of correction signals, the measurement error increases very quickly. Similarly, a quick increase in the measurement error is observed when a magnetic heading sensor used for correction stops working properly. This study aims to propose measurement of the roll angle for yaw angle correction.

AHRS algorithms were designed; typical maneuvers were analyzed. The method was verified by simulation and in flight testing analysis. For quantitative analyses, a performance index was proposed.

The method enables reduction of the yaw angle error caused by the gyros bias error. This study presents the idea, results of simulations and flight testing data analysis and discusses advantages and limitations of the presented method.

The presented methodology can be implemented in AHRS systems for manned and unmanned aircraft.

This study enables more accurate measurement of the yaw angle in the case of missing correction signals.

Europe has adopted the Flight Path 2050 (FP2050) challenge demanding that by 2050, 90 per cent of the travelers are able to reach door-to-door destinations in Europe within four hours. A hypothesis can be formulated that without the Small Air Transport (SAT) system, optimized for short distances and for multiple but narrow passenger flows, this challenge cannot be met.

This paper defines design goals and necessary research focused on small aircraft concepts, as a required condition to fulfil the FP2050 challenge “90 per cent d2d 4h”.

The new small aircraft concepts have been defined as SAT Aircraft Family Program. Three demonstrators with common modules could be proposed: two using the same turboprop engine (first, one engine, 9 passengers; second, two engines, 19 passengers) and third demonstrator could be with a diesel hybrid engine.

The SAT Aircraft Family Program depends on demand optimized for specific regional features (passenger flows, passenger time value spectrum and infrastructure) and a set of matured technologies as a result of Clean Sky 2 (CS2) devoted to SAT.

This practical implications consist of developing on SAT technologies in CS2, deploying the demonstrators by the small aviation industry and launching an SAT system pilot phase.

FP2050 has changed the approach to a citizen-oriented from an atomized technologies taxonomy-oriented one. The challenge “90 per cent d2d 4h” also covers the needs of remote regions. This niche could be filled by the SAT system using the small aircrafts family.

The paper value is in defining entry requirements, answering how to build the SAT Aircraft Family Program satisfying the FP2050 challenge “90 per cent d2d 4h”.

This study aims to optionally-piloted aircraft is useful for in-flight tests of new automatic controller’s concepts. The safety of this kind of experiment is an issue addressed in this paper. The prediction of possible safety-influencing factors makes it possible to assess the pilot’s ability to effectively prevent safety risks.

The analysis in this research paper focusses on two cases of monitoring; similar control standards for both pilot in command and the monitoring pilot or technical systems in one of these tasks and dissimilar control standard when monitoring pilot is not familiar with a control manner of the pilot in command or of the automatic control system. The increased workload is expected in the last case as the result of additional activities determined theoretically in the presented analysis. Details of the possible threats are obtained by simulation tests with various factors influencing the safety of landing. In addition to determining threats, the analysis includes the possibility of in time threat detection and preserving action.

The results show that the safety pilot has a different task than the pilot in command and needs to be familiar with the general principles of automatic controller operations and the particular algorithm being tested. Although commonly used landing procedure is relatively error-tolerant, new landing procedures for use in some specific conditions need more precise control and additional safety pilot preparation. Additional information presented to both the pilot in command and the safety pilot may increase mode and state awareness and reduce reaction time in an emergency condition.

In-flight tests of non-standard control algorithms there is a need to include additional preparation of the equipment and safety pilot. The research in this paper illustrates how to determine threats and safety-critical moments during the experimental flight can be observed. The danger is mitigated by the safety pilot, if familiar with both proper and improper operations of the controller and how the pilot in command should detect and predict danger caused by the tested control system.

The presented method of analysis combines the human factor with various technical aspects. The results obtained illustrate the real tasks of the person supervising the operation of the automatic control system and the role of a human as a safety pilot.

Mike Oakey, who joined Specialised Mouldings Ltd., of Huntingdon as Chief Executive of the newly formed Aerospace Division in January, has been appointed Director of Operations and Deputy Managing Director.