Several general effects of boundary conditions and their adequate description at structural dynamic computational simulation constitute the main subject of the discussion. First, an analytical model of elastically supported beam was considered to evaluate the effects of support compliance to the basic dynamic characteristics. Second, a more complex model of a body with elastic support was simulated. Some general properties of structure dynamics were analysed.
For the characterization of vehicle acceleration, in addition to such common parameters as change of speed and acceleration in time, there should be applied one more parameter: change of acceleration increase in time. Change of acceleration increase in time jp progresses in four specific phases in each gear: I – beginning of run where jp is growing rapidly to the maximum value of the gear; II – jp reduction from the maximum value to the stabilized value; III – speeding up with stabilized value jp and IV – shifting when jp value is changing in a wide range to the maximum negative value and then to zero.
The research is focused on the development of an Unmanned Aircraft System. One of the design process steps in the preliminary design phase is the calculation of the flight envelope for the Unmanned Aircraft System air vehicle. The results obtained will be used in the further design process. A flight envelope determines the minimum requirements for the object in Certification Specifications. The present situation does not impose any Certification Specification requirements for the class of the Unmanned Aircraft System under the development of the general European Union trend defined in the road map for the implementation of the Unmanned Aircraft System. However, operation in common European Aerospace imposes the necessity for regulations for micro class systems as well.
Margarita Urbaha, Arnis Križus and Deniss Kreisberg
This article analyses the reasons for the reduction of insulating resistance, processes influencing them and isolation diagnostic methods. It provides a short description of electrical safety situation on ships with isolated neutral electrical power systems. It also covers the methods of protecting personnel from electric shock or preventing ignition or arching damage at the fault location with the help of fault current compensation. Principal fault current compensation circuit diagrams are analysed by using the minimum value and time of transient fault current as criteria.
Pjotrs Trifonovs-Bogdanovs, Anastasia Zhiravetska, Tatjana Trifonova-Bogdanova and Konstantin Mamay
Inertial system errors in case of using the new structural correction method have been determined. Inertial system errors, which determine the kinematic parameters of aircraft movement, are finally generated in the computing circuit. This is the part of inertial system structure which is presented as a closed loop with a feedback. The forward circuit of the main loop consists of several velocity and distance integrators connected in series. Accelerometer signal corrections are calculated in the feedback loop. New corrective circuits have been introduced to the inertial system structure. And the errors of the changed system have been determined. The structural corrective circuits got signals from exterior onboard navigation systems. The conducted research has shown that the use of structural corrective circuits in some cases leads to a considerable decrease of inertial system errors. It means that the new structural method of inertial system correction provides positive results. Further research of inertial system errors should be conducted for the case of its full structure.
Silva Andersone, Lauris Miķelsons and Ibrahim Arandas
The Theoretical Aspects of Erroneous Actions During the Process of Decision Making by Air Traffic Control evaluates the factors affecting the operational decision-making of a human air traffic controller, interacting in a dynamic environment with the flight crew, surrounding aircraft traffic and environmental conditions of the airspace. This article reviews the challenges of air traffic control in different conditions, ranging from normal and complex to emergency and catastrophic. Workload factors and operating conditions make an impact on air traffic controllers’ decision-making. The proposed model compares various operating conditions within an assumed air traffic control environment subsequently comparing them against a theoretically “perfect” air traffic control system. A mathematical model of flight safety assessment has been proposed for the quantitative assessment of various hazards arising during the process of Air Traffic Control. The model assumes events of various severity and probability ranging from high frequency and low severity up to less likely and catastrophic ones. Certain limitations of the model have been recognised and further improvements for effective hazard evaluation have been suggested.
Mareks Šlihta, Vladimirs Šestakovs and Ramachandran Karunanidhi
This article presents a mathematical model estimating the probability of successful completion of the aircraft’s flight in case of aviation equipment failure in flight. This paper shows the relationship between the aircraft’s automatic control system and flight safety. The calculations of probability are made for the successful completion of the flight on Boeing 737 aircraft when the automatic control system has failed.
Pjotrs Trifonovs-Bogdanovs, Artūrs Levikins, Vadims Kirillovs and Zarif Zabirov
An analytical bank-and-climb gyro unit supplies the flight crew with information about aircraft angular movement relative to the local vertical. This article describes the particular principles of unit operation providing a step by step explanation of principles governing the operation of the analytical bank-and-climb gyro unit and provides a kinematic scheme of the unit. The article also gives an insight into the occurrence of errors in the bank-and-climb gyro unit as well as explains their significance.
Aleksandrs Urbahs, Rima Mickevičienė, Vasilij Djačkov, Kristīne Carjova, Valdas Jankūnas, Mindaugas Zakarauskas, Natalia Panova and Dita Lasmane
The paper gives brief description of the conventional and innovative hydrography survey methods and constraints connected with the realization. Proposed hydrographic survey system based on the use of Unmanned Aerial and Maritime systems provides functionality to conduct hydrographic measurements and environment monitoring. System can be easily adapted to fulfil marine safety and security operations, e.g. intrusion threat monitoring, hazardous pollutions monitoring and prevention operations, icing conditions monitoring.
Sigurdur Hrafn Gislason, Ruta Bogdane and Inese Vasiļevska-Nesbita
ACMI flight crews spend considerable time away from home on outstations. This study suggests that this long term stay carries its own considerations in regards to rest recovery with practical implications for Fatigue Risk Management as prescribed by ICAO. Four recovery experiences, Work Detachment, Control, Relaxation and Mastery, are identified and correlated with 28 crew behaviours on base. The results indicate improvement considerations for airline management organizing a long term contract with ACMI crews, in particular to increase schedule stability to improve the crew member’s sense of Control.