Ultralight Aircraft Research Articles

Proposition of a More Suitable Type of Aircraft for Basic Pilot Training

The topic of the article is the assessment of aeronautical technology for basic pilot training. The article discusses the possibility of using ultralight aircraft in basic pilot training. It shall include an analysis of the current system and the state of pilot training. Furthermore, the aeronautical technology currently used in basic pilot training is specified. It focuses on the calculation of the price of the flight time of the aircraft types currently in use and makes a proposal for the introduction of newer, more suitable types of aircraft, which should be introduced into the basic training system. In our work, we also refer to the calculation of the price for the operation of the aircraft and the economic evaluation of the newly proposed aircraft type and its comparison with the types of aircraft technology used so far for basic pilot training.

EXPERIMENTAL ANALYSIS OF ULTRALIGHT AIRCRAFT TYRE BEHAVIOUR UNDER AIRCRAFT LANDING PHASE

The aim of the research described in this paper is analysis of the deformation of the aircraft tyre subjected to static load. Based on the results of experimental tests with a different value of inflation pressure, favorable pressure conditions for use in the tyre of an ultralight aircraft were determined. The deflection characteristics of the tyre depending on the nominal pressure was determined using the digital image correlation technique. In the range of loads not leading to excessive tyre deflection, quite linear relation between vertical deflection and vertical force is observed. The safe minimum pressure in tyre loaded with a force of 12 kN is 2.5 bar. The experimental results will be used to select a shock absorber for a 600 kg ultralight, light sport aircraft commercialised by the company Ekolot (Krosno, Poland).

Low Cost Avionics System for Ultralight Aircraft

Abstract The article presents a low cost avionics system for ultralight aircraft and paraplanes. The system contains Attitude and Heading Reference System, Air Data Computer and Primary Flight Display. Communication between units is via Wi-Fi. In the article design description was presented, as well as laboratory tests results. They are promising and the system is ready for in flight testing.

An Adaptive Sensor Framework for Gyrocopter-Based Optical Remote Sensing: Introduction and Applications

Airborne remote sensing with optical sensor systems is an essential tool for a variety of environmental monitoring applications. Depending on the size of the area to be monitored, either unmanned (UAVs) or manned aircraft are more suitable. For survey areas starting at several square kilometers, piloted aircraft remain the preferred carrier platform. However, a specific class of manned aircraft is often not considered: the gyrocopter-type ultralight aircraft. These aircraft are less expensive to operate than conventional fixed wings. Additionally, they are highly maneuverable, offer a high payload and a long endurance, and thus perfectly fill the niche between UAVs and conventional aircraft. Therefore, the authors have developed a modular and easy-to-use sensor carrier system, the FlugKit, to temporarily convert an AutoGyro MTOsport gyrocopter into a full-fledged aerial remote sensing platform mainly for vegetation monitoring. Accordingly, various suitable optical sensor systems in the visible (VIS), near-infrared (NIR), and longwave infrared (LWIR) were explicitly developed for this carrier system. This report provides a deeper insight into the individual components of this remote sensing solution based on a gyrocopter as well as application scenarios already carried out with the system.

Požiadavky na harmonizáciu údržby ultraľahkých lietadiel

The exact definition of an Ultralight Aircraft is still very diverse, especially in the European region. Internationally, there are various Ultralight Aircraft (UL) classes with nationally varying certification regulations. Accordingly, Ultralight Aircraft is used colloquially ore or less comprehensively for Very Light Aircraft or Light-Sport Aircraft. However, they are subject to much stricter certification nd maintenance regulations. This paper aims to compare the current legal situation in the European Union countries, extract the best practices, and propose how a new “AMC & GM” should define the laws and regulations to create the best possible vironment for UL airworthiness. This paper is written based on information and directions published on the websites of the esponsible uthorities of the respective countries, as well as communication with these authorities and first-hand knowledge obtained by conducting numerous interviews with people in the field of UL maintenance. The results indicate how different each country egulates the maintenance and continuing airworthiness of ULs and how important a harmonised regulation would be. It is specially important to have clarity as with larger aircraft and thus also to prevent numerous accidents and hazardous situations in the future.

Simulation Study of a Composite Landig Gear of Ultralight and Very Light Aircraft

There is a need to design new, lighter aircraft structures, which has a direct impact on the safety and costs of aircraft maintenance. One of basic parts of an aircraft is ites landing gear, whose main functions are to enable taxiing, safe landing, take-off, and to assist the remainder of ground operations. Landing gear failures are usually related to metallurgy, processing, environment, design, and causes of overload. These are conditions that can be prevented using modern methods to calculate the strength of such a landing gear in various conditions. The paper presents stages of a simulation study of the fixed three-wheeled spring landing gear for an ultralight aircraft. Analysis of forces acting on the landing gear during drop test and their implementation by numerical computer methods allowed for the creation of a model in the CAD (Computer-Aided Design) tool and its FEA (Finite Element Analysis). These results were compared between a modeled classic spring landing gear and the one made of composite materials. The further goal of the research will be to build a drop test stand for a small landing gear used in airplanes and drones. This method has a significant impact on simplifying the design of the landing gear, its modeling, and optimization.

Experimental Analysis of the Influence of the Application of TiN, TiAlN, CrN and DLC1 Coatings on the Friction Losses in an Aviation Internal Combustion Engine Intended for the Propulsion of Ultralight Aircraft

Currently, there are many methods of reducing the friction losses of the main components of an internal combustion piston engine. The operating conditions of internal combustion piston engines intended for the propulsion of ultralight aircraft differ significantly from those prevailing in the case of using these engines for the propulsion of vehicles. There are many studies on the influence of selected anti-wear coatings on the friction coefficients when using various lubricants, measured via tribometers. Unfortunately, the conditions obtained in the laboratory significantly differ from those prevailing in an engine operating under external conditions. The study investigated the influence of a change in the tribological parameters of TiN, TiAlN, CrN and DLC1 anti-wear coatings on the moment of resistance to the piston movement of an aircraft engine. The operating parameters of a real engine working in an aircraft were simulated. The main focus was on the coating layers of the sliding surfaces of the piston rings and the cylinder running surface. The properties of the coatings affect the correlation of the scale of the adhesion and cohesion phenomena of the oil to the opposite planes, and this determines the nature of the changes in the moment of resistance to engine motion. As it is commonly known, with an increase in the value of the maximum pressure of the working medium in the combustion chamber, the share of mixed friction in liquid friction increases, similar to the high oil temperatures occurring in aircraft engines. Therefore, there is a justified need to supplement the research in the field of analyzing the characteristics of the torque of resistance to motion for these engines, in particular in the field of the usable rotational speeds of the crankshaft. Applicable anti-wear systems based on selected coatings can significantly improve operational safety and noticeably reduce fuel consumption.

In-Flight Tests of Intruder Detection Vision System.

In the near future, the integration of manned and unmanned aerial vehicles into the common airspace will proceed. The changes taking place mean that the safety of light aircraft, ultralight aircraft and unmanned air vehicles (UAV) will become an increasing problem. The IDAAS project (Intruder Detection And collision Avoidance System) meets the new challenges as it aims to produce technically advanced detection and collision avoidance systems for light and unmanned aerial vehicles. The work discusses selected elements of research and practical tests of the intruder detection vision system, which is part the of IDAAS project. At the outset, the current formal requirements related to the necessity of installing anticollision systems on aircraft are presented. The concept of the IDAAS system and the structure of algorithms related to image processing are also discussed. The main part of the work presents the methodology developed for the needs of dedicated flight tests, its implementation and the results obtained. The initial tests of the IDAAS system carried out on an ultralight aircraft generally indicate the possibility of the effective detection of intruders in the airspace with the use of vision methods, although they also indicated the existence of conditions in which this detection may prove difficult or even impossible.

Pengaruh Variasi Persentase Campuran Polymer Polyester dan Vinyl Ester Terhadap Kekuatan Tegangan Lentur

Polymer mixture of polyester and vinyl ester is widely used in engineering fields such as for car bumpers, boat bodies, ultra-light aircraft wings, wind turbine blades and others. One of the requirements to meet the application aspects in the engineering field is the ability of the material to withstand bending loads. For this reason, it is necessary to test the flexural stress characteristics of the mixture of the two polymers of unsaturated polyester and unsaturated vinyl ester. The aim is to find out which of the two polymer blends obtains superior flexural resistance properties from each of the polymers with respect to the blend percentage. To determine the flexural stress value of the polyester and vinyl ester mixture, a flexural stress test was carried out with reference to the standard flexural test or the bending test used based on ASTM D 790 by varying the composition of the mixture 100%: 0%, 90%: 10%, 80%: 20%, 60%:40%, and 0%:100%. From the results of the bending stress test on specimens with variations in the composition of polyester and vinyl ester with the hand lay-up method, the highest bending stress value is found in the composition of 60% polyester and 40% vinyl ester, which is 126.88 MPa ( an increase in maximum flexural strength of 255%)

Analysis of Torque Waveforms in Two-Cylinder Engines for Ultralight Aircraft Propulsion Operating on 0W-8 and 0W-16 Oils at High Thermal Loads Using the Diamond-Like Carbon Composite Coating

Analysis of Torque Waveforms in Two-Cylinder Engines for Ultralight Aircraft Propulsion Operating on 0W-8 and 0W-16 Oils at High Thermal Loads Using the Diamond-Like Carbon Composite Coating

Experimental investigation of the stable water isotope distribution in an Alpine lake environment (L-WAIVE)

Abstract. In order to gain understanding on the vertical structure of atmospheric water vapour above mountain lakes and to assess its link with the isotopic composition of the lake water and with small-scale dynamics (i.e. valley winds, thermal convection above complex terrain), the L-WAIVE (Lacustrine-Water vApor Isotope inVentory Experiment) field campaign was conducted in the Annecy valley in the French Alps during 10 d in June 2019. This field campaign was based on an original experimental synergy between a suite of ground-based, boat-borne, and two ultra-light aircraft (ULA) measuring platforms implemented to characterize the thermodynamic and isotopic composition above and in the lake. A cavity ring-down spectrometer and an in-cloud liquid water collector were deployed aboard one of the ULA to characterize the vertical distribution of the main stable water isotopes (H216O, H218O and H2H16O) both in the air and in shallow cumulus clouds. The temporal evolution of the meteorological structures of the low troposphere was derived from an airborne Rayleigh–Mie lidar (embarked on a second ULA), a ground-based Raman lidar, and a wind lidar. ULA flight patterns were repeated several times per day to capture the diurnal evolution as well as the variability associated with the different weather events encountered during the field campaign, which influenced the humidity field, cloud conditions, and slope wind regimes in the valley. In parallel, throughout the campaign, liquid water samples of rain, at the air–lake water interface, and at 2 m depth in the lake were taken. A significant variability of the isotopic composition was observed along time, depending on weather conditions, linked to the transition from the valley boundary layer towards the free troposphere, the valley wind intensity, and the vertical thermal stability. Thus, significant gradients of isotopic content have been revealed at the transition to the free troposphere, at altitudes between 2.5 and 3.5 km. The influence of the lake on the atmosphere isotopic composition is difficult to isolate from other contributions, especially in the presence of thermal instabilities and valley winds. Nevertheless, such an effect appears to be detectable in a layer of about 300 m thickness above the lake in light wind conditions. We also noted similar isotopic compositions in cloud drops and rainwater.

Modelling and Experimental Validation of a Hybrid Electric Propulsion System for Light Aircraft and Unmanned Aerial Vehicles

This article presents a numerical model of an aeronautical hybrid electric propulsion system (HEPS) based on an energy method. This model is designed for HEPS with a total power of 100 kW in a parallel configuration intended for ultralight aircraft and unmanned aerial vehicles (UAV). The model involves the interaction between the internal combustion engine (ICE), the electric motor (EM), the lithium battery and the aircraft propeller. This paper also describes an experimental setup that can reproduce some flight phases, or entire missions, for the reference aircraft class. The experimental data, obtained by reproducing two different take-offs, were used for model validation. The model can also simulate anomalous operating conditions. Therefore, the tests chosen for the model validation are characterized by the EM flux weakening (“de-fluxing”). This model is particularly suitable for preliminary stages of design when it is necessary to characterize the hybrid system architecture. Moreover, this model helps with the choice of the main components (e.g., ICE, EM, and transmission gear ratio). The results of the investigation conducted for different battery voltages and EM transmission ratios are shown for the same mission. Despite the highly simplified model, the average margin of error between the experimental and simulated results was generally under 5%.

Effect of using a Dynamic Absorber On Vibrations of an Opposed-Piston Ultralight Aircraft Engine

In this paper, vibrations reduction of piston engine of ultralight aircrafts was studied with considering a combination of experimental, analytical and numerical methods. Analytical equations of dynamic absorber were obtained. Afterward, experimental test was used to determine the system torque. Due to the difficulty of obtaining experimental data, the amount of angular acceleration and then velocity and angular displacement were calculated numerically using MATLAB software and verified with experimental results with a difference of less than 2%. Different components of the system were designed with reverse engineering method using SolidWorks software. After data transmission to Adams software, vibrational analysis of the system was performed and validated with analytical results with a difference of less than 1.91%. A suitable dynamic absorber was selected. The results showed that engine vibrations is reduced up to 40%.

A Systematic Approach for Evaluating the Adoption of Additive Manufacturing in the Product Design Process

Additive Manufacturing (AM) technologies have expanded the possibility of producing unconventional geometries, also increasing the freedom of design. However, in the designer’s everyday work, the decision regarding the adoption of AM for the production of a component is not straightforward. In fact, it is necessary to process much information regarding multiple fields to exploit the maximum potential of additive production. For example, there is a need to evaluate the properties of the printable materials, their compatibility with the specific application, redesign shapes accordingly to AM limits, and conceive unique and complex products. Additionally, procurement and logistics evaluations, as well as overall costs possibly extending to the entire life cycle, are necessary to come to a decision for a new and radical solution. In this context, this paper investigates the complex set of information involved in this process. Indeed, it proposes a framework to support and guide a designer by means of a structured and algorithmic procedure to evaluate the opportunity for the adoption of AM and come to an optimal design. A case study related to an ultralight aircraft part is reported to demonstrate the proposed decision process.

Study on Improvement in Operation and Management of Ultra-light flying device Civil Complaints Management System for Ultralight Aircraft

Study on Improvement in Operation and Management of Ultra-light flying device Civil Complaints Management System for Ultralight Aircraft

Models of Signals, Algorithms and Errors of Instrumental Channels of the Air Data System Based on the Vortex Method

The enhanced complexity and weight of conventional air data systems based on aerometric, aerodynamic, and vane sensor methods in using them on ultralight and small aircraft, is justified. The study reveals the theoretical foundations of the vortex method for measuring the incident air flow parameters and its implementation in the original system based on the vortex method using the original vortex sensor of the aerodynamic angle and true air speed. The algorithms of formation and processing of primary informative signals in the measuring channels of the aircraft air data system based on the vortex method are presented. The models are obtained and the quantitative estimation of instrumental errors of measuring channels is carried out.

Aerosol optical properties as observed from an ultralight aircraft over the Strait of Gibraltar

Abstract. An unprecedented scientific flight was conducted over the Strait of Gibraltar to study the optical properties of the atmospheric aerosols from the sea surface to the lower free troposphere within the framework of the southern Spain experiment for spaceborne mission validation (SUSIE). A Rayleigh–Mie lidar was installed on an ultralight aircraft (ULA) for vertical (nadir) and horizontal line-of-sight measurements. This experiment took place on 13 August 2011 in parallel with continuous observations with a N2-Raman lidar from the coastal site of San Pedro Alcantara (∼ 50 km north-east of Gibraltar). Significant differences were observed between the optical properties of the aerosol layers sampled over the Strait of Gibraltar and San Pedro Alcantara. These differences are related to the surface–atmosphere interface in the planetary boundary layer and the origins and transport processes in the lower free troposphere. A significant contribution of terrigenous aerosols originating from the Iberian Peninsula is highlighted over the two areas. These polluted dusts are identified with lidar ratios (LRs) ∼45±8 sr higher than those of Saharan aerosols sampled during the same period (<34 sr) at 355 nm. Furthermore, the particle depolarization ratio is derived with values of ∼ 10 %–15 % for the polluted dust and >20 % for the Saharan dusts. The difference in LRs is the opposite of what is usually assumed for these two types of aerosols and highlights the need to update the classification of aerosols in terms of LR to be used in the inversion of vertical profiles from future spaceborne missions embedding a lidar operating at 355 nm.

CRW 13 – the new generation radio altimeter: the concept, design, and tests

PurposeThe 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.Design/methodology/approachThe new design of the device consists of integral antennas and signal processor for smart digital signal filtering.FindingsAs 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.Practical implicationsThe 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.Originality/valueAt 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.

Upscaling UAS Paradigm to UltraLight Aircrafts: A Low-Cost Multi-Sensors System for Large Scale Aerial Photogrammetry

The use of unmanned aerial systems (UASs) has rapidly grown in many civil applications since the early 2010s. Nowadays, a large variety of reliable low-cost UAS sensors and controllers are available. However, contrary to ultralight aircrafts (ULAs), UASs have a too small operational range to efficiently cover large areas. Flight regulations prevailing in many countries further reduced this operational range; in particular, the “within visual line of sight” rule. This study presents a new system for image acquisition and high-quality photogrammetry of large scale areas (>10 km²). It was developed by upscaling the UAS paradigm, i.e., low-cost sensors and controllers, little (or no) on-board active stabilization, and adequate structure from motion photogrammetry, to an ULA platform. Because the system is low-cost (good quality-price ratio of UAS technologies), multi-sensors (large variety of available UAS sensors) and versatile (high ULA operational flexibility and more lenient regulation than for other platforms), the possible applications are numerous in miscellaneous research domains. The system was described in detail and illustrated from the flight and images acquisition to the photogrammetric routine. The system was successfully used to acquire high resolution and high quality RGB and multispectral images, and produced precisely georeferenced digital elevation model (DEM) and orthophotomosaics for a forested area of 1200 ha. The system can potentially carry any type of sensors. The system compatibility with any sensor can be tested, in terms of image quality and flight plan, with the proposed method. This study also highlighted a major technical limitation of the low-cost thermal infrared cameras: the too high integration time with respect to the flight speed of most UASs and ULAs. By providing the complete information required for reproducing the system, the authors seek to encourage its implementation in different geographical locations and scientific contexts, as well as, its combination with other sensors, in particular, laser imaging detection and ranging (LiDAR) and hyperspectral.

저고도 운용 항공기를 위한 기상정보의 필요성에 관한 연구

According to the Ministry of Land, Infrastructure and Transport press release ('18.12.21.) The amendment of the Aviation Business Act will reduce the capital requirements for aviation leisure operators and make it easier to enter aviation leisure businesses by improving regulations on small air transportation business. In addition, as the scale of the UAV(Unmanned Aerial Vehicle) sector is expected to increase globally, the dramatic increase in low altitude operating aircraft, including this, must be taken into account. The low altitude aircraft category is divided into small airplanes, helicopters, light aircrafts and ultra-light aircrafts, and instructors include school instructor pilots and student pilots, military and national helicopter pilots, and aviation leisure operators. In case of low altitude aircraft, there are cases of canceling operations due to low visibility and low clouds, and aircraft accidents due to excessive operation and sudden weather phenomenon. Therefore, in order to prevent low-altitude aircraft accidents, a safe flight plan based on weather conditions and weather forecasts and more accurate and local weather forecasts and weather forecast data are needed to prepare for the rapidly changing weather conditions.