This article discusses the advantages and disadvantages of transition to QNH pressure. The analysis of various factors affecting the flight safety has been conducted. A comparative analysis of the two types of altitude reading while approaching the airport has been carried out. The first type is the altitude reading relative to the airfield when at an aerodrome surface an altimeter altitude is equal to zero. This pressure is called QFE. The second one is estimated relatively to the sea level; in this case the aerodrome elevation must be taken into account. Such pressure is called QNH. These both pressures are used in aviation. Historically, QFE pressure was used in the USSR, and after the disintegration of the Soviet Union this type of pressure was used during takeoff and landing. In the mid - 2000s, the majority of Russian airlines began to use the foreign aircraft, mainly the airplanes produced by Boeing and Airbus Companies. Since these aircraft are produced in Western countries, they use QNH pressure, so there are some difficulties of correct altitude setting while approaching an aerodrome, this causes an aircraft descent below the level prescribed by STAR, consequently, decent below minimum safe altitude. The conclusion of necessary transition to QNH pressure was made using the example of aircraft. The article also explains why the transition to QNH pressure flights in the Russian Federation is a top priority and a necessary step for maintaining proper level of flight safety.

The article considers the formalization of the service technology of departing passengers into network model, which is a good basis for improving the service technology, monitoring the performance that determines the process duration and service optimization in cost and resources. The article shows the formalization result of the service technology of departing passengers into network model; the critical path is found, and the duration of service is determined. In order to find the critical path of the network graph it is recommended to apply the Dijkstra algorithm. It allows us to identify all critical paths from the initial vertex to the final one if there are several. Improving the service process is possible by reducing the performance duration on the critical path and upgrading the service technology. When servicing the departing passengers, there may be factors that lead to the flight departure delay due to the fault of the passenger transportation organization. While analyzing the service for departing passengers, additional work to eliminate the flight delay factors is considered. The service network model is shown in case of untimely removal of the baggage, belonged to the passenger who has not arrived for the flight; the service duration has been determined and critical path activities requiring special attention have been identified. The results analysis provides a list of critical path activities for several reasons of departure violation. It is concluded that it is necessary to reduce the performance duration of critical path graph to ensure the departure of a scheduled flight. Optimization of network model involves consideration of several possible service technologies of departing flight, taking into account the additional work to eliminate the factors leading to the flight delay from the airport and then creation of such service technology which would provide the minimum expenses at given service process duration.

Airport Collaborative Decision Making (A-CDM) is a collaborative process management tool in accordance with agreed procedures to improve the performance of all partners in all situations. The A-CDM system for the airport is a part in the control process cycle of arriving and departing aircraft flows, ground handling operation and management along the routes of the flight. The introduction of the A-CDM element "Adverse Conditions" at Sheremetyevo airport makes it possible to control the reduction of the airport capacity and facilitates the process of its rapid recovery. Data on the increase in predictability after the introduction of the element A-CDM "Adverse Conditions" at Sheremetyevo airport are: predictability time of the landing aircraft is – 98.7% (increased by 12.9%); predictability time of employment parking areas (PA) is – 93.1% (increased by 17.1%); predictability time of the taxiing aircraft is – 92.6% (increase by 2.5%); predictability of the departure time of the aircraft – 97.2% (increased by 2.1%); punctuality of scheduled the aircraft departure – 83.55% (increase by 0.3%); punctuality of the departure aircraft at the estimated time – 94% (increased by 1.2%); number of delayed flights more than 15 minutes – 16.45% (decrease by 22.6%); average taxiing time from planting to the arrival – 7.5 minutes (a reduction of 7%); average taxiing time from the departure to take-off aircraft – 11.9 min (decrease by 3%). "The agreement on approval of scenarios for calculating take-off and landing operations to ensure the maximum capacity of the runway complex" was developed jointly PJSC "Aeroflot" and the specialists of Sheremetyevo ATC center, is tied to the level of capacity change, which increases the flexibility of the planning system.

The efficiency of the helicopter main rotor in the hover mode is very important, because this mode essentially determines the performance characteristics of the helicopter. A feature of the helicopter rotor aerodynamics is a significant inductive blade influence that highly defines its aerodynamic characteristics. The problem of the influence of the blade twist and spatial geometric layout of the main rotor on its aerodynamic characteristics in the hover mode for a fixed value of the rotor solidity has been considered in this article. As a criterion of efficiency of the rotor in the hover mode relative efficiency (FoM – Figure of Merit) is used. The results are obtained by numerical simulation based on the nonlinear vortex blade model of the rotor, developed at the Helicopter Design Chair of the MAI. The model allows taking into account a complicated spatial shape of the free vortex path of the rotor blades that determines their inductive interaction. As the example of a four-blade main rotor with rectangular blades in plan, the influence of the value of the blades twist on the efficiency in the hover mode is studied. For different values of the rotor thrust, the values and ranges of the blade twist angles are determined, providing the maximum positive effect of the efficiency increase in hovering. For a fixed value of the blade twist, the rotor solidity, and the same operating conditions, the effect of various schemes and configurations of rotor on its efficiency in hover mode is studied. A single rotor with a different number of blades (from 2 to 6), an X-shaped rotor, coaxial rotor and rotor with crossed blades type "synchropter" are considered. The values of the efficiency increase in hovering depending on the rotor layout in comparison with the two-blade rotor are obtained. The comparative analysis of inductive velocities and streamlines for the "synchropter" rotor scheme, coaxial rotor scheme and its equivalent single rotor scheme is presented. The obtained results can be useful at the stage of preliminary design of vertically taking-off aircraft when selecting the parameters of their main rotor system.

The article deals with the issue of providing electric power to the first category receivers in the emergency mode of the power supply systems operation of perspective and modernized aircraft. The analysis of the published scientific works performed both in Russia and abroad, and aimed at solving problems of analyzing abnormal operations mode, synthesizing power supply systems and controlling them in order to prevent dangerous consequences is carried out. The authors considered the ingenious technical solutions aimed at providing the necessary quality power supply for the first category receivers in the emergency operation modes of the aircraft power supply systems for the safe completion of flight and landing. The research analysis and generalization of data on the technical characteristics of units and devices developed by the world's leading manufacturers of aviation equipment and used as emergency sources of electrical power on board modern civil aviation aircraft has been completed. The advantages and disadvantages of each technical solution are determined, as well as limitations to the area of their application are formed. The analysis of perspective emergency sources of the electric power including those, which previously were not applied in aviation because of their insufficient technical perfection, for example, hydrogen electrochemical generators is carried out. Based on the performed analysis, a solution which allows improving the operating modes of the electrical batteries is proposed. The offered solution makes it possible to increase the reliability and durability of electrical batteries, as well as the power supply duration of the first category receivers from them.

The aircraft integrated control system reconfiguration laws under failures of actuators, calculated disregarding physical constraints on control surfaces saturation, can lead to a complete loss of aircraft controllability and stability. Despite the large number of scientific publications in this field, practical systematic results have been obtained only for SISO (single input – single output) systems. Problems of the convergence of iterative algorithms restricting the set of admissible solutions and the conservatism of the reconfiguration laws designed using weight matrices do not allow solving this problem in general. For complex MIMO (multi input – multi output) systems there is still no widely accepted universal approach. In this work, control surfaces constraints are regarded in terms of the power of reconfiguration control. It is shown that by slight modification of pseudoinverse (optimal) solution it is possible to obtain approximate pseudoinverse (suboptimal) solutions with priory known minimum power (compensation matrix norm) and error (residual matrix norm) of the reconfiguration for a given degree of approximation. This allows for a multistep consistent reduction in power and increasing in error of reconfiguration, until an acceptable solution is obtained. By providing the greater reconfiguration error at each step we have additional freedom in reducing the reconfiguration power. This leads to a decrease in the amplitude of the deviations of the control surfaces, to which the signals from the failed control channels are redistributed. The simulation example of the aircraft integrated control system reconfiguration under the stabilizer’s actuator failure is presented. It is shown that the pseudoinverse reconfiguration problem solution leads to the significant ailerons’ constraints violation and the loss of aircraft controllability. Regarding control constraints solution reduces several times the deviation of the control surfaces and provides an effective problem solution in the permissible power and error reconfiguration range.

The International Civil Aviation Organization (ICAO) has published documents regulating the measures aimed to increase the intensity of flights. It is supposed to introduce qualitatively new principles of air traffic management based on the technical achievements in the field of communication, navigation and surveillance. The existing dispatching service technology is based on the principle of regulating the flow of aircraft through the feedback mechanism. The plan of the airspace utilization is used as the model for the management process. Deviations in the measurand of the aircraft movement from the calculated values can create prerequisites for potentially conflict situations and require the intervention of air traffic controller. The adjustment tool is a new distribution of the aircraft in their place, time and height. Following the instructions of the dispatcher, the pilot either proceeds to the bypass route, or changes either the altitude or speed. Minimal interference in the actions of the pilot is one of the criteria for assessing the controller’s work. The essence of ICAO's proposals is in the transition from the "tracking" system which responds to the deviations from the balanced model to the control system which predicts the tendencies to changing the air situation in real time. In order to realize this intention, every ground center and every crew should have consistent information about the real situation in the air and its development, so that each new intention (decision) is modeled, agreed on by the colleagues and fixed in flight plans. To reach the success in co-regulation of the situation it is important to have computer support in the field of aeronautical maintenance of decision-making, as well as high-speed algorithms for assessing the current parameters of the air traffic servicing process, such as handling capacity of aerodromes and terminals related to the changes being prepared. The article discusses the dynamic model of collective formation and flow maintenance using system-wide information. The model is built as a multi-channel system with priorities. Analytical estimates of the throughput are given. Criteria for the assessment are the indicators of the probability of failure and the average waiting time for maintenance by controller (refuses include the direction of the aircraft to the alternate aerodrome, repeated circle of landing, delayed departure, etc.). The proposed formulae are confirmed by the results of simulation computer experiments and statistical modeling.

Force-measuring equipment is widely used in all sectors of the economy, primarily in industry. Force measurement is used to determine loads affecting operation capability of various types of equipment and their components to ensure safe operation as well as during tests and research of the systems and mechanisms. The most effective are devices consisting of an elastic element and a transducer of its deformation into an electric signal. An analysis of known force-measuring devices shows that at a large range of loads the most effective form of the elastic element is the ring. As electric transducers of deformation in similar gauges, capacity, inductive, vibrating-wire and strain gauges are used. The disadvantages of existing devices are slow response, suitability for a narrow range of loads, low contact reliability, non-linearity. There are significant prospects of the circular type sensors development with optoelectronic signal transducers, which allows increasing significantly the efficiency, reliability and accuracy of force measurement. The compensation principle is supposed to be used in the dynamometric gauges where as a control input variable, a value of an elastic element deformation is used. The control algorithm of a compensation scheme of undesirable discrepancies of a control variable is made so that to reduce a deformation value to naught. Due to this fact, operation of a dynamometric gauge based on the principle of force compensation is carried out with a lot of accuracy. The construction of the gauge contains a sensing zerobody, an amplifier, feedback and a measuring device.

The article gives a brief analysis of the transport industry condition in the context of the provision of passenger transportation services, considers the existing problems of enterprises in the market economy conditions such as: the lack of guarantees and responsibility of suppliers to consumers, and vice versa (delays and non-payments, defaulters); forced lending to enterprises by transport companies and agencies, that means the use of banking services in the non-banking sector; the lack of developed for all types of transport domestic inventory and distribution systems based on the uniform requirements; the weakness of the existing system of control and prevention of dangerous trends, which leads to crises in the market and the chain reaction of insolvency of the participants. In this regard the article proves the justification for the creation of a unified system of control and regulation of transport services, aimed at providing control and monitoring of the conditions of the enterprises and the system as a whole, preventing dangerous trends and crises; providing mutual guarantees and protection of risks of both suppliers and consumers; creating a universal payment center; development of criteria for assessing market participants (ratings of solvency, reliability and other assessment methods). All this taken together will prevent negative consequences for transport companies. The structure of such a complex system, necessary subsystems and their functionality are considered. Specific solutions are proposed, whose implementation will allow constructing elements of a single control system on the basis of existing and operating in the industry inventory and distribution systems, as well as the mechanism of regulation and effective impact on the transport industry enterprises.

The present day globalization in economy is closely connected with the development of air transport-one of the fastest growing sectors of economy, which provides long-distance transport, primarily to passengers. The mobility of population has increased and as a consequence the single transport space has been formed. After the crisis of 2015–2016 the economy of civil aviation is characterized by the rapid growth, increased passenger turnover, a high percentage of seat occupancy and the change in the structure of the air transportation market. The state of the air transportation market is characterized by globalization, deregulation, information and privatization. The services which air companies offer to the market are related to a high-tech product. At the same time, modern conditions require airlines to take measures to improve their performance, taking into account the internal and external factors affecting this business, as well as a set of incentive measures for workers in this industry. Thus, the article discusses the process of industry deregulation, gives several examples of market functioning models, highlights their main characteristics and shows options for making managerial decisions. Efficiency evaluation is a prerequisite condition for the implementation of airline development strategies. The principles of market economy required the restructuring of relations in distributive system and material incentive. In this regard, we summarize the experience of several labor remuneration decisions, as an integral part of airline management. The article gives an overview of the modern air transportation market characteristics, identifies the problems and prospects for its development. The relevance of the article is stipulated by the expanded presence of airlines in the world market and, as a consequence, by the necessity to investigate the up-to-date trends in market development, exposure the main factors that affect the competitiveness of air companies. The article is of interest for aviation experts as well as for readers who are keen on aircraft.

The task to provide flight safety is solved both at the stage of design and manufacture of aircraft and during its operation. Flight safety is influenced by three groups of factors: a human factor, a technical factor and marginal ambient conditions. In spite of the fact that only about 3% of aviation accidents are caused by marginal ambient conditions, in many cases there was a combination of the human factor as the main one with the availability of the accompanying unfavorable external conditions, especially marginal weather conditions. The article provides a comparative analysis of a flight safety factor in commercial civil aviation in the Russian Federation and the United States and analyzes accident statistics caused by adverse meteorological conditions. Since the greatest number of accidents related to marginal weather conditions occurred with helicopters, the article has highlighted the possibility of increasing helicopter flight safety by creating a methodology for risk assessment associated with the influence of adverse weather conditions before the flight operation. Risk assessment techniques, such as the ICAO Risk Assessment Matrix, the CFIT checklist, FRAT, have been analyzed and the feasibility of using the FRAT methodology has been demonstrated. On the basis of the FRAT methodology after updating the section "Operating conditions of the aircraft", a risk assessment methodology for the forthcoming flight of helicopters was obtained. A risk level admissibility scale for the forthcoming flight was proposed to interpret the obtained values of the risk level.