Motor Glider Research Articles

Analysis of injuries in aircraft accident victims in 2002–2022 based on the resources of the Jagiellonian University Department of Forensic Medicine in Kraków = Analiza obrażeń ofiar katastrof lotniczych w latach 2002–2022 na podstawie danych pochodzących z materiałów Zakładu Medycyny Sądowej Uniwersytetu Jagiellońskiego w Krakowie

Aim: The study aimed to analyse the most common injuries of victims of aviation accidents and compare it with the most recent literature. Methods and materials: Retrospective analysis of autopsy protocols of aircraft crash victims from the Forensic Medicine Department from years 2002–2022. The case selection has been made by two independent researchers. After applying the exclusion criteria 27 cases were obtained. Further searched for features that the bodies of victims had in common. There were analysed sex, age, circumstances of the incident, injuries, presence of psychoactive substances (alcohol, drugs), and blood concentration of carboxyhemoglobin. Results: Among 27 cases we found 19 airplane crashes, 4 glider accidents, 3 motor glider accidents, and one helicopter crash. The 1 case had no information about the type of aircraft. The injuries that emerged in each of the victims were typical results of direct impact forces. The most common were rupture of the lungs 63.0 % (n = 17/27), heart 55.6% (n = 15/27), liver 51.9% (n = 14/27), aorta 40.7% (n = 11/27) and spleen 29.6% (n = 8/27). Common bone traumas included fractures of the ribs 77.8% (n = 21/27) upper limbs 77.8% (n = 21/27), skull 74.1% (n = 20/27), pelvis 59.3% (n = 16/27) and spine 51.9% (n = 14/27). Injuries of the cervical spine occurred in victims who violently tilted their heads back. Conclusions: In most cases, the immediate cause of death was extensive multi-organ injuries, followed by thermal burns or brain injuries. In almost half of the victims, the presence of carboxyhemoglobin in the blood indicates that they were alive during the crashes. Knowledge of injury patterns can improve aviation safety and guide in reconstructing the mechanisms and sequences of the accidents.

Relationship Between Wingspan and Fuselage Length in Aircraft According to Engine Types

The study aims to explain the size relationship between wingspan and fuselage length, which are the two basic design parameters that a designer is most curious about. Within the scope of the study, the relationship between take-off mass, fuselage length and wingspan of a total of 601 aircraft was questioned for single-piston, twin-piston, turboprop, and jet aircraft types. Power correlations were used for mass-based sizing of wingspan and fuselage length. In mass-based sizing, bad correlations were found for fuselage length for single-piston airplanes and good correlations for turboprops and jets. In terms of wingspan to fuselage length ratio (b/lfus) jets showed a more pronounced trend, ranging from 0.7 to 1.1, while other aircraft types showed different trends, ranging from 0.9 to 1.7. In general, racer, homebuilt, aerobatic, and light transport aircraft have low b/lfus ratios, while motor gliders, firefighters, patrol, and agricultural aircraft have high b/lfus ratios. The study is valuable in that it fills a gap in the literature by considering the relationship between wingspan and fuselage length both with correlations over mass and by revealing statistics according to aircraft types over proportional relationship.

Обнаружение лесных пожаров по изображениям, полученным с БПЛА

Forest fires represent a serious natural risk causing economic losses, loss of life and significant environmental damage. In different countries of the world, including in Russia, research has been carried out to develop solutions for the detection and subsequent monitoring of forest fires. The most common ones are remote fire detection and monitoring systems, both groundbased (mobile or stationary), airborne (airplanes and helicopters), and satellite-based ones. These systems are highly efficient in data collection and fire detection, but for small areas. However, wildfires can cover large areas, making known approaches unsuitable for optimal spatial coverage. To overcome this limitation, unmanned aerial vehicles (UAVs) are proposed, that have proven to be useful due to their maneuverability, allowing the implementation of remote information acquisition in any direction, the flight route planning strategies, etc. Ultimately, they provide a low-cost alternative to established approaches for real-time detection and monitoring of wildfire areas. This article discusses a technique for early detection of forest fires based on UAV image processing, which is based on the previous works of the authors. The technique involves the use of computer vision algorithms for processing images received from an unmanned motor glider (UMG). The UMG route (for example, circular or elliptical) can be designed in such a way that it is possible to regularly receive information about a large area. The flight time of the UMG can be up to several hours. When transmitting the received images to the processing center, it becomes possible to extract information about the detection of a forest fire and subsequently control its spread.

Comparison of Pollutants Emission for Hybrid Aircraft with Traditional and Multi-Propeller Distributed Propulsion

Due to the dynamic development of environmentally friendly aircraft propulsion, the paper describes the effect of distributed propulsion on the emission and fuel consumption changes of aircraft in comparison to aircraft with traditional propulsion. A distributed propulsion is a propulsion composed of a set of units located on the leading edges of the wings or on the fuselage, generating a thrust symmetrically distributed on both sides of the fuselage. The analysis was based on the technical data of AOS H2 motor glider. During the tests for the adopted geometry of distributed propulsion, the improvement of airframe aerodynamic parameters was determined by conducting a CFD flow analysis. Based on the energy method, the flight range and duration were determined for the aircraft with distributed propulsion. It occurred that they increased by 19% compared to the initial variant—traditional propulsion. For the adopted energy source—Wankel AG-407TGi engine, the emissions of CO, CO2, and NO in the exhausts were measured. After the application of distributed propulsion, the emissions and fuel consumption were reduced by 16%. The research conducted showed that the application of distributed propulsion instead of traditional propulsion can bring measurable environmental benefits. Conducting further research on multi-criteria optimization of aircraft structures may bring further benefits in terms of improving aircraft performance and environmentally friendly indicators.

Design and simulation of an Unmanned Aerial Vehicle based on a motor glider concept

Due to the miniaturization of optoelectronic devices, the increase in computing power, and the improvement of control systems and navigation systems, Unmanned Aerial Vehicles (UAVs) have become an indispensable tool in areas such as agriculture, industry (critical infrastructure inspection), and surveying. These systems are available in fixed-wing and rotary-wing (multiple rotors) configurations. The multiple rotor system is characterized by advantages such as vertical take-off and landing and simplicity of the structure design and control algorithm. Still, there are also disadvantages: the short flight time and very high energy consumption. Based on the requirement for a platform with high reliability and high flight range, the paper proposes a solution for fixed-wing UAVs with an extended flight time, self-launching, short landing, and optimized energy consumption. The presented solution is inspired by the model of the Romanian glider IS-28B2 produced by ICA Ghimbav, which has been redesigned and optimized to become a 1:10 scale UAV type glider. The paper presents the 3D model design, simulation, and optimal autopilot integration for this robotic aerial system.

Computer Vision Method for Forest Fires Detection Based on RGB Images Obtained by Unmanned Motor Glider

The article proposes a method (algorithm) of forest fire detection by means of RGB images obtained by using an unmanned aerial vehicle (motor glider). It includes several stages associated with background detection and subtraction and recognition of fire areas by means of RGB colour space. The proposed method was tested using images of forest fires. It is proposed to use unmanned aerial vehicles capable to monitor large areas continuously for several hours. The results of calculations are shown, which demonstrate that the proposed method allows us to detect areas of images occupied by forest fires and may be used in automatic forest fire monitoring systems.

A rotating piston engine with electric generator in serial hybrid propulsion system for use in light aircraft

Analysis of the possibility of using a rotary engine based electric generator to propell a powered sailplane. The paper presents analysis of utilising Wankel type enine as a power input for an electric generator in the motor glider propulsion system. This generator would be a part of the propulsion system of a hybrid motor glider using the AOS 71 motor glider airframe. In the research, the rotational characteristics of the LCR 407ti wankel engine were determined experimentally. Driving torque run, power and fuel consumption were determined as a function of engine speed. The obtained results are presented in diagrams. The conceptual diagram of the hybrid drive is presented. The electric generator was selected and its effectiveness, as well as the effectiveness of entire propulsion system was assessed from the motor glider's performance point of view. Basing on the research conducted, conclusions were drawn and there were indicated the objectives and directions of further research on hybrid propulsion with specific aerodynamic and mass limitations of the aircraft

Use of Electric Motors in the Context of Glider Aviation

Abstract In sailplane aviation, I attach great importance to the achieved aerodynamic parameters due to the main idea of sailplane flights, which is the flight of a sailplane without external energy supply for staying in the air and only in favourable weather conditions, e.g. increasing thermal movements of the air. Only during take-off, external devices, such as a winch or a towing plane, can be used. Therefore, the use of a propulsion installed in sailplanes and operating only during take-off is a very convenient solution. This is a step towards facilitating the access to flying for a wider group of people due to the reduction of costs related to the take-off processes, and also increases the level of safety of sailplane flights by enabling the use of propulsion at critical moments of the flight. The study presents the current trends in the development of gliding, in particular motor gliders. Additionally, as a result of research works, the energy storage system was shown, which is the weakest element of the system, and at the same time the one with the greatest development potential.

In Situ Measurements of Wind and Turbulence by a Motor Glider in the Andes

AbstractA Stemme S10-VT motor glider was equipped with a newly developed sensor suite consisting of a five-hole probe, an inertial navigation and global navigation satellite system, two temperature sensors, and a humidity sensor. By design, the system provides three-dimensional wind vector data that enable the analysis of atmospheric motion scales up to a temporal resolution of 10 Hz. We give a description of components and installation of the system, its calibration, and its performance. The accuracy for the measurement of the wind vector is estimated to be on the order of 0.5 m s−1. As part of the Southern Hemisphere Transport, Dynamics, and Chemistry (SouthTRAC) field campaign, 30 research flights were performed from September 2019 to January 2020. We present statistical analysis of the observations, discriminating pure motor flights from soaring flights in the lee waves of the Andes. We present histograms of flight altitude, airspeed, wind speed and direction, temperature, and relative humidity to document the atmospheric conditions. Probability density functions of vertical air velocity, turbulence kinetic energy (TKE), and dissipation rate complete the statistical analysis. Altogether, 41% of the flights are in weak, 14% in moderate, and 0.4% in strong mountain wave conditions according to thresholds for the measured vertical air velocity. As an exemplary case study, we compare measurements on 11 September 2019 to a high-resolution numerical weather prediction model. The case study provides a meaningful example of how data from soaring flights might be utilized for model validation on the mesoscale and within the troposphere.

Energy Conversion System and Control of Fuel-Cell and Battery-Based Hybrid Drive for Light Aircraft

The paper presents a power electronic conversion system and its control for a fuel cell and a battery-based hybrid drive system for a motor glider. The energy conversion system is designed in such a way that the fuel cell gives power equal to the electric drive power demand for horizontal flight, whereas during motor glider take-off and climbing, the fuel cell is supported by the battery. The paper presents the power demand related to the assumed mission profile, the main components of the hybrid drive system and its holistic structure, and details of power electronics control. Selected stationary experimental test results related to the energy conversion and drive system are shown. Some results related to the aircraft tests on a runway are presented.

Design, Development, and Performance of a 10 kW Polymer Exchange Membrane Fuel Cell Stack as Part of a Hybrid Power Source Designed to Supply a Motor Glider

A 10 kW PEMFC (polymer exchange membrane fuel cell) stack consisting of two 5 kW modules, (A) and (B), connected in series with a multi-function controller unit was constructed and tested. The electrical performance of the V-shaped PEMFC stack was investigated under constant and variable electrical load. It was found that the PEMFC stack was capable of supplying the required 10 kW of electrical power. An optimised purification process via ‘purge’ or humidification, implemented by means of a short-circuit unit (SCU) control strategy, enabled slightly improved performance. Online monitoring of the utilisation of the hydrogen system was developed and tested during the operation of the stack, especially under variable electrical load. The air-cooling subsystem consisting of a common channel connecting two 5 kW PEMFC modules and two cascade axial fans was designed, manufactured using 3D printing technology, and tested with respect to the electrical performance of the device. The dependence of total partial-pressure drop vs. ratio of air volumetric flow for the integrated PEMFC stack with cooling devices was also determined. An algorithm of stack operation involving thermal, humidity, and energy management was elaborated. The safety operation and fault diagnosis of the PEMFC stack was also tested.

Comparative analysis of pollutants emission by classical and distributed propulsions applied on the AOS motor glider

Comparative analysis of harmful compounds emission of classical and distributed propulsions applied on the AOS motor glider, taking into account the perspective of the development of hybrid propulsions. A novel path is indicated by so-called distributed aircraft propulsion. The advantages and disadvantages of this type of solutions are presented, as well as the conceptual design of the distributed propulsion for the AOS 71 motor glider. In the paper there were compared the emissions of harmful compounds generated by a hybrid power unit developed for the airframe of AOS 71 motor glider – traditional propulsion, so-called focused (one-propeller) and dispersed propulsion (multi-propelled). Functional diagrams of both types of propulsions solutions are presented. Construction and aerodynamic constraints of both propulsions are discussed and comparative analysis is made. In the traditional version of the propulsion (so-called focused propulsion). the propeller is driven by an Emrax 228 electric engine with effective parameters: N = 55 kW, M = 120 Nm. The power source is a battery set with a capacity of 16 Ah and a range extender powered by a LCR 407ti rotating piston engine with maximum power of 28 kW. In the variant of the distributed propulsion. Ten electric engines of AXI 8120 type were used to drive small propellers arranged along the wingspan. The power source in this variant is analogous to the variant with the Emrax electric engine. For the adopted variant of the flight mission of the motor glider. a flight trajectory model was developed, which was used to determine the load of the power unit. In laboratory conditions. emission tests of both propulsions were conducted. The results are summarized in charts and discussed in the conclusions.

Analysis of the possibility of using an engine with a rotating piston as the propulsion of an electric generator in application to a motor glider propulsion

Analysis of the possibility of using an engine with a rotating piston as the propulsion of an electric generator in application to a motor glider propulsion The paper presents an analysis of the possibilities of application of a rotating piston engine (Wankel type) as a propulsion for an electric generator in the motor glider propulsion system. This generator would be a part of the propulsion system of a hybrid motor glider using the AOS 71 motor glider airframe. In the research, the rotational characteristics of the LCR 407ti engine were determined experimentally. Driving torque run, power and fuel consumption were determined as a function of engine speed. The obtained results are presented in diagrams. The conceptual diagram of the hybrid drive is presented. The current generator was selected and the effectiveness of the generator and the entire propulsion were assessed from the motor gliders performance point of view. On the basis of the conducted research, conclusions were drawn and there were indicated the objectives and directions of further research on hybrid propulsion with specific aerodynamic and mass limitations of the aircraft

Comparative analysis of combustion engine and hybrid propulsion unit in aviation application in terms of emission of harmful compounds in the exhausts emitted to the atmosphere

Comparative analysis of combustion and hybrid propulsion unit in aviation application in terms of emission of harmful compounds in the exhausts emitted to the atmosphere. For the propulsion of the AOS 71 motor glider, two types of propulsion were planned as de-velopment versions. The first analysed propulsion is based on a combustion engine, but of the Wankel type (LCR 814 engine with the power of 55 kW). The second designed propulsion is an hybrid based on a LCR 407 combustion engine with a power of 28 kW, which is connected in series with an electric generator propelling the engine (Emrax 228 engine), total power of the propulsion is 55 kW. The comparison of emissions of harmful compounds emitted to the atmosphere generated by the combustion and hybrid power unit intended for assembly in the AOS 71 motor glider, assuming various loads and methods of hybrid propulsion control, was made. The tests were conducted in laboratory conditions. Several different programs were designed to simulate different energy management methods in a hybrid system, depending on the predicted mission and load of the motor glider. On the basis of laboratory tests, exhaust emission was determined from both propulsions as a function of rotational speed and load. Then, based on the assumed flight trajectory and collected test data, the emission for both propulsions variants was determined. The values of emission parameters were compared and the results were presented in diagrams and discussed in the conclusions

Analysis of the Application of Distributed Propulsion to the AOS H2 Motor Glider

Abstract The paper describes the selection of a distributed propulsion for the AOS H2 motor glider (selection of engines, their number, and propellers) and determination of its performance. This analysis is related to the research conducted on environment friendly and hybrid propulsions in various research centres. The main aim of the analyses conducted is to increase the performance of vehicles powered by electric motors. The batteries have a low density of energy, i.e. the ratio of mass to cumulated energy. Instead of a battery set, it is possible to apply a hybrid-electric system, where the combustion engine works as a generator or an electric-hydrogen generator, where the hydrogen cell supports a small set of batteries. One of such flying vehicles, fitting in this trend, is the AOS H2 motor glider built at the Rzeszow University of Technology in cooperation with other universities. It is a hybrid aircraft, equipped with a hydrogen cell, which together with a set of batteries is a source of electricity for the Emrax 268 electric motor. To increase the vehicle's performance (the range and flight duration), it is possible to use a distributed propulsion. This type of propulsion consists in placing many electric motors along the wingspan of the aircraft. Appropriate design of such a system (propeller diameters, engine power, number of engines) can improve the aerodynamic and performance parameters of the airframe. An analysis of the performance for the selected flight trajectory for this propulsion variant was conducted and compared to the performance of the AOS H2 motor glider equipped with traditional propulsion. The consumption of hydrogen was also determined for both systems. The results obtained were presented in the diagrams and discussed in the conclusions.

Innovative Scaled Test Platform e-Genius-Mod—Scaling Methods and Systems Design

Future aircraft design highly depends on the successful implementation of new technologies. However, the gap between conventional designs and new visions often comes with a high financial risk. This significantly complicates the integration of innovations. Scaled unmanned aircraft systems (UAS) are an innovative and cost-effective way to get new configurations and technologies in-flight. Therefore the Institute of Aircraft Design developed the e-Genius-Mod taking into account all relevant similitude requirements. It is a scale model of the electric motor glider e-Genius. Since the Reynolds number for the free-flight model cannot be adhered to, an airfoil was developed with lift-to-drag and lift-to-angle-of-attack courses reproducing the full-scale e-Genius flight characteristics. This will enable testing and assessment of new aviation technologies in a scaled version with an opportunity for free-flight demonstration in relevant environment.

Some aspects of gaseous hydrogen storage and the performance of a 10-kW Polymer Electrolyte Membrane Fuel Cells stack as part of a hybrid power source

A 10-kW polymer electrolyte membrane fuel cell (PEMFC) stack was designed and built as part of a hybrid power source to supply a motor glider. The power of the PEMFC stack reached ∼10 kW for the electrical parameters I = 61 A, U = 153 V. The time of operation of the stack under an electrical load close to 10 kW was strongly dependent on the pressure of the hydrogen fuel stored composite tanks, which could be varied from 220 bar for 30 min to 700 bar for 80 min. It was found that the electrical efficiency of the constructed 10-kW PEMFC stack was greater than 50%.

Evaluation of the Suitability of the Strain-Gauge Method for Measuring Deformations during the Fatigue Tests of Aviation Composite Structures

Abstract The paper discusses the results of selected fatigue tests of a motor glider’s insulated spar structure. The results of the experimental tests were used to assess the potential of the strain-gauge method for diagnosing the spar damage involving the unbolting of one of metal fittings in the spar pin. The usefulness of the deformation measurement method in the composite structure diagnostic process was confirmed, while simultaneously drawing attention to the need for conducting a process optimizing the number of sensors and their distribution on a tested object, in the context of the sensitivity of diagnostic signals received.

A study of reflected sonic booms using airborne measurements

In support of ongoing efforts to bring commercial supersonic flight to the public, the Sonic Booms in Atmospheric Turbulence (SonicBAT) flight test was conducted at NASA Armstrong Flight Research Center. During this test, airborne sonic boom measurements were made using an instrumented TG-14 motor glider, called the Airborne Acoustic Measurement Platform (AAMP). During the flight program, the AAMP was consistently able to measure the sonic boom wave that was reflected off of the ground, in addition to the incident wave, resulting in the creation of a completely unique data set of airborne sonic boom reflection measurements. This paper focuses on using this unique data set to investigate the ability of sonic boom modelling software to calculate sonic boom reflections. Because the algorithms used to model sonic boom reflections are also used to model the secondary carpet and over the top booms, the use of actual flight data is vital to improving the understanding of the effects of sonic booms outside of the...

DETAILED AND HIGHLY ACCURATE 3D MODELS OF HIGH MOUNTAIN AREAS BY THE MACS-HIMALAYA AERIAL CAMERA PLATFORM

Abstract. Remote sensing in areas with extreme altitude differences is particularly challenging. In high mountain areas specifically, steep slopes result in reduced ground pixel resolution and degraded quality in the DEM. Exceptionally high brightness differences can in part no longer be imaged by the sensors. Nevertheless, detailed information about mountainous regions is highly relevant: time and again glacier lake outburst floods (GLOFs) and debris avalanches claim dozens of victims. Glaciers are sensitive to climate change and must be carefully monitored. Very detailed and accurate 3D maps provide a basic tool for the analysis of natural hazards and the monitoring of glacier surfaces in high mountain areas. There is a gap here, because the desired accuracies are often not achieved. It is for this reason that the DLR Institute of Optical Sensor Systems has developed a new aerial camera, the MACS-Himalaya. The measuring unit comprises four camera modules with an overall aperture angle of 116° perpendicular to the direction of flight. A High Dynamic Range (HDR) mode was introduced so that within a scene, bright areas such as sun-flooded snow and dark areas such as shaded stone can be imaged. In 2014, a measuring survey was performed on the Nepalese side of the Himalayas. The remote sensing system was carried by a Stemme S10 motor glider. Amongst other targets, the Seti Valley, Kali-Gandaki Valley and the Mt. Everest/Khumbu Region were imaged at heights up to 9,200 m. Products such as dense point clouds, DSMs and true orthomosaics with a ground pixel resolution of up to 15 cm were produced. Special challenges and gaps in the investigation of high mountain areas, approaches for resolution of these problems, the camera system and the state of evaluation are presented with examples.