The legal regulation, and hence, the training system in the field of unmanned aircraft systems (UAS) in the Russian Federation, the European Union and the United States is based on the unmanned aerial vehicles (UAV) rating with respect to UAS maximum take-off weight (MTOW) and their purpose (method of use). In this regard, small-unmanned aircraft (sUAS) are identified – in our country up to 30 kg, in the EU and the USA up to 55 lbs (25 kg) and UAV with larger weight. In the USA and Europe, the training of remote pilots for sUAS is differentiated based on the degree of risk that UAV can represent for public safety. Thus, the training of remote pilots to use UAVs with MTOW less than 25 kg (55 lbs) in a sparsely populated area during daylight hours under the conditions of visual range is conducted in the online format, the result of which is taking tests. In the United States and Europe, the UAV application with MTOW more than 25 kg (55 lbs) or performing UAV operations, presenting a potential risk for public safety, requires more comprehensive and long-term training of remote pilots. In the Russian Federation, UAS personnel training is conducted in educational organizations according to different programs, which vary significantly depending on a specific type of aviation UAVs refers to: State, Civil or Experimental. UAS personnel training programs for various aviation types are not harmonized, which leads to the failure to credit previously received education in training to perform activities in another aviation type. The article describes the analysis results of the international and national experience, perspectives for the development of the UAS personnel training system, as well as formulates the proposals concerning further development of the national system for UAS specialists training.

   The paper proposes a technology for automated video-based observation (VBO) of a drogue-sensor in the problem of aerial refueling. The technology is based on the use of a passive optoelectronic system and incorporates the logic of automated refueling observation of a refueling process using algorithms for the automatic detection and tracking of a drogue-sensor, a methodical apparatus for suboptimal linear filtering of the observed process under the conditions of spatial and temporary non-stationarity of the refueling process, algorithms for automatic correlation detection and tracking of a drogue-sensor using suboptimal filtering. An analysis of the design of experimental foreign systems for autonomous aerial refueling is carried out. The choice of the algorithm for the functioning of the synthetic vision system is substantiated. It is established that the main observation procedures: detection, capture for tracking and determination of the current drogue coordinates with a given rate and quality should be performed automatically, the pilot-operator takes part in the operation of the synthetic vision system in case of capture errors or mistracking. The statement of the problem for automated VBO of a drogue-sensor is formulated. A structural-logical diagram of the automated observation process, including the detection and tracking of a drogue, as well as decision-making by the pilot in various situations, is proposed. A modeling complex for a synthetic vision system operation is presented. The results of experimental studies of the synthetic vision system efficiency are presented. Based on the developed technology and the results of evaluating the effectiveness of automated observation algorithms, a strategy for performing autonomous refueling in conditions of various turbulence is proposed, while, during weak turbulence, a successful engagement is provided by tracking the center of drogue oscillations, in turn, under conditions of severe turbulence, a successful engagement can be provided by tracking a drogue controlled according to the synthetic vision system data.

   The given article represents the study of the influence of color, surface finish and shape of dents on the reliability of 3D surface dents visual inspection, which are formed due to damage to epoxy composite materials reinforced with carbon fiber resulted from impacts. This article provides an analysis of the influence of surface color of aircraft structural components made of composite materials on the reliability of a visual inspection. The test results are given. Using these values, it is possible to determine the cross-section profiles of surface defects caused by impacts with energy within the range from 5 J to 80 J. The new designs of aircraft, which have been put into service thus far, feature 50 % and more composite materials of the airframe mass and use monolithic carbon fiber composite panels for the fuselage skin. Carbon fiber composite is particularly sensitive to the post-impact compressive strength reduction, and the operating aircraft environment is characterized by an array of sources of impact damages. Samples of the surface appearance of real composite structures of the aircraft on impact is the confidential information. Currently available literature concerning impact damage to composite materials, focuses on impact testing using hemispherical impact elements of typical diameters Ø 15mm, Ø 20 mm or Ø 25 mm. Testing information regarding larger diameter samples is not provided. There is no published research into impact damages to monolithic, fully finished carbon fiber composites.

   In-flight engine failure has always been a hazardous situation in case of a single-engine aircraft associated with losing altitude and making a landing within the available gliding range. In the event of a multi-engine aircraft, this situation improves markedly due to the potential flight continuation. The necessary conditions to continue a flight are available excess thrust, satisfactory aerodynamic performance, and a fixed-wing control. If the half of engine thrust is lost, which adversely affects a rate of climb, the most critical flight modes are the take-off and go-around procedures performed at low altitudes using the engine asymmetric thrust. Ensuring flight safety in these modes requires extensive experimental studies in wind tunnels to simulate the basic flight envelope with an inoperative engine.

   The aim of studies is the effect of a critical engine failure on the aerodynamiccharacteristics of an aircraft model as well as ensuring the required efficiency of the flight controls to dampen the yaw and roll moments that arise during an asymmetric thrust flight.

   The complexity of solving the problem is determined by the necessity of recovering from the substantial yaw, roll moments and by a significant decrease in the wing lifting efficiency along with an increase in a drag force which limits a climb rate and aircraft control. This article presents an analysis of the effect of critical engine failure on the aerodynamic characteristics of a light twin-engine transport aircraft model in the wing take-off and landing configurations. The aircraft aerodynamic configuration is made according to the classic pattern with the high-mounted tapered wing and deck-type empennage. The high lift devices comprise a double-slot hinged flap with a fixed deflector. The aircraft is equipped with a loading ramp with a relatively short flat rotatable part of the lower fuselage surface. Experimental studies of the longitudinal and lateral characteristics of the model with installed simulators of a power plant were carried out in TsAGI low-speed wind tunnel T-102. The analysis of engine failure effect on the model aerodynamics was executed in changing the load factor within the range B = 0.3…2. The capabilities to dampen the yaw and roll moments, using the primary flight controls (rudder and ailerons), were determined.

   In recent years, the urgency of the problem of launch vehicles load-bearing elements optimal design has continued to grow. One of the widespread structural designs is an anisogrid lattice structure made of polymer composite materials. Such structures are mass-produced and used as load-bearing bodies of space vehicles or fuselage compartments of atmospheric aircraft of advanced structural design. Until now, the weight and parameters of the skins used in products of rocket and space equipment have not been considered when solving optimal design problems, and the design problem has been reduced to optimizing lattice structures without skin. At the same time, the very use of skins for both atmospheric aircraft and load-bearing elements for space applications is a fairly common practice. However, not considering the availability of skin when designing a lattice load-bearing shell can lead to a significant increase in the mass of the structure with skin when applicable. The paper presents a method for the optimal design of lattice structures without ring ribs, but with the metal skin available, which can significantly reduce the weight of such structures, increasing the mass efficiency of products made of polymer composite materials used in aircraft. A confirmation of the results obtained with the help of an analytical solution and the results of a numerical experiment, obtained by modeling using the finite element method, is given. It is expected that the use of the proposed approach by considering the contribution of the skin response can lead to mass saving of the shell anisogrid structure up to 30 % compared with the methods of optimal design of lattice anisogrid structures currently used without considering the availability of skin in the design of the product.

   The issue of using vortex generators to improve the take-off and landing characteristics of a transport category aircraft has been considered. Three directions have been analyzed. The first: the installation of vortex generators on the nacelles of the main engines to increase the maximum value of the lift coefficient in landing modes. The second: the installation of vortex generators on the upper surface of the flap to increase the lifting characteristics of the wing by improving the flow around the flap. The third: the installation of vortex generators in the tail unit to increase the efficiency of control surfaces and reducing handling speeds. Examples of the use of vortex generators in each of the directions are given. It is shown that the improvement of the aerodynamic characteristics of the aircraft is possible in the presence of wing separation boundaries on the lifting surfaces in flight operating modes and the elimination of these zones by installing vortex generators. The results of computational studies, experiments in wind tunnels, as well as data from flight tests of an experimental aircraft confirming the effectiveness of using vortex generators are presented. The concept of increasing their stability by installing vortex generators in places with maximum flow velocity is proposed. Considering this concept, new locations for installing vortex generators on the upper surface of the flap, as well as on the fin of an experimental aircraft for repeated flight tests have been selected. The installation of vortex generators on the fin involves increasing the efficiency of the rudder to reduce the handling speeds. The possibilities of optimizing the parameters of the installation of vortex generators are considered. Recommendations are given on the choice of shape, size, and angles of their installation, depending on the tasks solved with the help of vortex generators and considering the possible increase in drag from their installation.