The statistics on the production and development of passenger airplanes in the world is presented in this article for the first time. The methods for obtaining the results are described, uncertainties of the results are estimated. It is specified what exactly is considered to be a passenger airplane. It is shown that only 60,000 passenger airplanes were built during the entire 20th century. This is less than 3% of the total production of airplanes of all classes. Their total capacity amounts less than 5 million people, or less than a thousandth of the world’s population by the end of the last century. These 60,000 airplanes provided unprecedented mobility of the population. It was revealed that the leading role in the passenger airplane manufacturing belonged to the USA, the USSR took a steady second place. The ups-and-downs in airplane production are described, including the recessions during the Great Depression, World War II and the global economic decline (in the USSR, the USA and other countries) in the early 1960s, which was replaced by a rapid increase in output. It is indicated that the number of airplanes produced in the last third of the 20th century remained approximately constant, but their average capacity was growing rapidly, which largely ensured the explosive growth of air transportation during this period. The dynamics of the dead weight per one passenger is given. The dynamics of the number of the new passenger airplane models is presented. It is shown that for the last 30 years of the century their number was approximately constant, and almost all the models that reached the test stage were put into serial production. In the period between the world wars, however, about half of all models tested in flight remained prototypes. The change in the ratio of the number of airplanes by the number of engines is given. The renaissance of three-engine airplanes in the 1960s, the almost complete disappearance of singleengine passenger airplanes by the end of the century and the stable amount of a small proportion of four-engine airplanes for the last 30 years of the past century are noted.

Currently, attention of the aviation community and authorities is being increasingly focused on flight safety in the landing phase. It is accounted for the increased frequency of incidents in the final phase of flight and significant threats associated with the consequences of these events. The statistics of aviation accidents reveals that from 1959 to 2019, 55% of aircraft crashes in the world occurred in the phases of landing and takeoff. The given crashes resulted in 51% of all fatalities on board aircraft. In most cases, causes of these aviation accidents are involved with some kind of human error. Off-design conditions at an aerodrome also have a significant adverse effect on the aviation accident potential and severity. The increasing intensity of flights, airspace congestion, strict ATC-imposed restrictions, the necessity to perform a variety of procedures and general flight crew stress in conjunction with dynamically changing external conditions can disorient a flight crew and lead to a landing with a flight envelope overrange. The search for a solution in terms of preventing aircraft overruns is actively being conducted both by aviation authorities and aircraft manufacturers and operators. Within the framework of this review, the major external and operational factors, affecting the dynamics and the nature of the aircraft roll via the runway, are analyzed, including the context of several accidents that have occurred in recent years. In addition, the article emphasizes the methods to prevent and anticipate aircraft overruns based on the principles of active protection. In particular, the article examines the main operation aspects of onboard avionics systems installed on Boeing and Airbus aircraft and highlights the focus areas of their upgrading. Special attention is paid to the influence of the pilot and the possibility of taking his actions into account to predict an outcome of landing.

As a result of jet fuel oxidation, insoluble sediments, called resins or high-temperature deposits, are formed. They significantly reduce the chemmotological reliability of aircraft engine fuel system units, i.e., fuel metering equipment, fuel-oil coolers, fine fuel filters, etc. The main factors that intensify the jet fuel oxidation processes are fuel quality and meeting specifications as well as its temperature. In this regard, aviation fuel supply enterprises constantly monitor indicators of the thermal aviation fuel stability. The widely used domestic method for assessing the thermal oxidative aviation fuel stability is the technique under static conditions (Thermal Jet Fuel Stability – TJFS), the foreign one is the dynamic technique (Jet Fuel Thermal Oxidation Test – JFTOT). Opinions concerning the use of a particular method for an objective assessment of the thermal aviation fuel stability are divided. The article considers the main provisions with respect to the jet fuel stability, overviews the methods and indicators, characterizing the thermal oxidative aviation fuel stability, provides statistical data on the long-term use of the static (TJFS) and dynamic (JFTOT) methods for assessing the quality of domestic TS-1 and RT fuel grades for subsonic aircraft supplied to an airline. It is shown that the use of the dynamic method (JFTOT) with the current operation parameters is not relevant.

Currently, the large number of aircraft accidents is associated with the loss of control in flight and a controlled flight into terrain. It frequently occurs due to a change of flight conditions, relatively which a preparation for departure was carried out, and involves the necessity to reroute efficiently in the conditions of increased psychophysiological load and time constraint for decisionmaking. Generated thunderstorm cells on route, artificial or natural obstacles, not considered while planning a route, can result in amending a flight plan, which was earlier accepted and implemented in the automatic, flight director or manual modes of control. The lack of comprehensive situational awareness is fairly a frequent cause of aviation accidents for general aviation aircraft. Aviation accidents of transport category aircraft are typically associated with incorrect crew actions when dangerous flight zones are detected along the route. The article represents an overview and analyzes modern onboard facilities to detect obstacles, as well as required pilot actions to reroute a flight for in-flight detected obstacle avoidance. The current level of avionics development provides situational awareness necessary for obstacles avoidance but requires timely, correct and sometimes non-obvious flight crew rerouting decisions. The algorithms used with robotic packages of various applications in related fields ensure the automatic rerouting for obstacle avoidance. They cannot be directly used or adapted for the implementation on board an aircraft due to the lack of consideration for aircraft specific features when obstacle avoidance routing, i.e., restrictions of control parameters (an angle of attack, overload, roll angle), capabilities of a control system (available rate of overload, available and maximally allowable angular rolling velocity, etc.). Therefore, the issue to develop a system to support pilot decisions for obstacle avoidance is relevant. It encompasses the synthesis of safe alternatives for obstacle avoidance which are optimal by a pilot-assigned criterion (minimum loss of time, minimum additional fuel consumption, etc.).

The article deals with the main advantages of railway transport in the field of tourist transportation and the capabilities of effective rolling stock use for organizing high-quality transport service and attracting new customers. Currently, the attention of a great number of transport industry scientists is focused on passenger transportation. The foundations of interaction between railway transport and the tourism industry are being formed. The importance of the railway tourism sector cannot be underestimated in terms of economic, social and environmental aspects of the society. There are advantages of railway transport compared with other modes of transport: the longest railway network in Europe, ability to transport a large number of passengers, use of railway cars as a hotel on wheels, high degree of reliability and safety, lack of dependence on weather conditions, high level of comfort and amenities on board, providing a choice of travel conditions depending on the carriage types and train categories, regularity. The development of the route network contributes to the increase in the competitive abilities of regional tourist destinations. At the same time, the key factors in choosing the method of organizing a tourist route are as follows: the volume of passenger demand for an assigned route, size of expenses, tour duration, etc. The field of tourist transportation is not limited to the use of rail transport only. Its collaboration with other types of transportation allows for maximum effect from tourist service while maintaining a high level of service. This interaction is one of the components of the tourism product aimed at addressing all the key aspects and stages of tour organization.

Modern trends in the aircraft development are associated with a significant increase in the level of its electrification. The emergence of new types of electricity consumers entails an increase in the power and number of consumers in the aircraft power supply system. At this stage of operation, direct control of the internal parameters (in particular, the parameters of reactive elements) of electricity consumers in the aircraft power supply system is not carried out. The aviation equipment control system is built taking into account the built-in system for monitoring the technical condition of the object. However, for greater efficiency, the built-in control can be supplemented with control capabilities through digital intelligent power distribution systems (local load control center). During the operation of aviation electrical equipment, the values of its parameters change relative to the nominal values. Deviations of equipment parameters from the nominal values should not exceed the specified values, which are determined by the operational technical documentation. Input impedances of secondary power supply sources can be investigated in a mode characterized by transient processes in the investigated component of aircraft equipment. Based on the experimental data of voltage and input current at the stage of transients in equivalent circuits of secondary power supplies, it is proposed to determine the values of the parameters of reactive elements. Changing the values of reactive elements gives information about the technical condition of the input stages of electrical energy receivers. This makes it possible to monitor the process of degradation of their properties or to diagnose a failure in the event of an abrupt change in reactive parameters. This method is proposed to be used for diagnosing electrical equipment during its operation on board the aircraft. This work is devoted to the development of methods for determining the parameters of secondary power sources of aircraft electrical equipment, characterizing its reactive properties.

The development of modern heat-stressed aircraft engines is a complex process based on the advanced achievements of various branches of science and technology, including chemmotology. Each new generation of aircraft engines imposes stricter requirements on the quality of the aviation oils used to ensure the reliable operation, including engine oil systems, rotor bearings and other components. One of the important factors in reducing friction and wear-out of modern gas turbine engines is the use of high-quality oils with a high level of anti-wear and anti-friction properties which allow engines to operate under various relubrication intervals. In the domestic regulatory and technical documentation, the anti-wear properties of aviation oils are evaluated using a four-ball friction machine according to GOST 9490, and the anti-friction properties are not taken into account. The specified friction machine has a variety of disadvantages. In this regard, the authors evaluated the anti-wear and anti-friction properties of domestic aviation oils using a versatile vibro-tribometer which allows for the operational properties of oils to be researched under the modes that are the most characteristic for the actual operation of aircraft engines compared with parameters of oil tests by a four-ball friction machine. Unlike the four-ball friction machine, the vibro-tribometer design implements a contact - interaction scheme in a “ball-plate plane” friction pair. At the same time, a thermal chamber is installed on this application that provides constant heating of the friction pair and the tested lubricating oils to the required temperature (from 0 to 150 ℃). It has been found that IPM-10 aviation oil possesses the best anti-wear and anti-friction properties, and with an increase in the tested oil temperature, a proportional increase in wear-out in the “ball-plate plane” friction pair occurs.

The article presents the results of a study of the characteristics of the wake vortex of aircraft with turboprop engines. Using the example of the An-12 aircraft, it is shown that rotating propellers make a noticeable contribution to the propagation of the vortex trail behind the aircraft. This is proved by some studies, as well as numerous observations. It also describes a technique for studying the wake vortex of aircraft with propellers. The method is based on the method of discrete vortices. The relevance of such studies is due to the growing interest of carrier companies in aircraft with turboprop engines. It has been proven that when transporting passengers and cargo on such vessels over distances of 700–800 km, maintenance and fuel costs are reduced by about 30–40%. Therefore, the fleet of turboprop aircraft, such as An-22, An-70, An-12, as well as Tu-95, Il-38, C-130, etc., has been preserved so far. New turboprop aircraft are being developed and put into operation: A-400M, Il-114, Il-112M. The vortex trail behind such aircraft also poses a danger to other aircraft flying behind. A feature of the propagation of the wake vortex behind aircraft with propellers is the interaction of vortices coming off the airframe and vortices from the propellers. As a result, due to the rotation of all the screws in one direction, symmetry is broken in the propagation of vortices descending from the right and left halves of the wing. Therefore, it is important to understand how differently the vortices that descend from the airframe of an aircraft with turboprop engines behave. For the convenience of the study, the method of accounting for the effect of vortices from screws is integrated into a special calculation and software package, also based on the method of discrete vortices. In it, when calculating the characteristics of the wake vortex, the flight weight, speed and altitude of the aircraft, its flight configuration, atmospheric conditions, proximity of the earth, axial velocity in the core of the vortex and some other factors are taken into account. This complex has passed the necessary testing and state registration. A number of measures were carried out to validate and verify the developed complex, confirming the operability of the programs included in it and the reliability of the results obtained from it. The results of the study of the characteristics of the wake vortex behind the Antonov-12 aircraft in the form of vertical velocity spectra and fields of perturbed velocities at various distances from it are presented. It is shown that propellers noticeably affect the propagation of the wake vortex behind turboprop aircraft. This circumstance must be taken into account by the crews of aircraft flying behind such aircraft.