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The problem of implementing the landing of a maneuverable aircraft by a pilot on an undamaged section of a runway of minimum length is considered. A method of landing the aircraft is proposed, including movement along the landing glide path with minimum speeds and angles of attack of 12-14 deg., the release of the landing parachute before touching the runway with the main wheels so that by the time the wheels touch the ground, the parachute fully opens, lowering the nose wheel and subsequent braking with maximum deceleration. A simplified mathematical model is considered that makes it possible to estimate the length of the run and the results of calculations for various parameters of the landing mass and the height of the release of the braking parachute. The results of such landings in flight tests are presented and compared with the results of calculated estimates. The calculated and experimental results obtained allow us to speak about the fundamental feasibility of the task of landing on a runway section limited in length.

The article analyzes the effectiveness of methods for monitoring motor vehicles during operation. The relevance of the study lies in the fact that the braking system is an important element responsible for the safe operation of the car. Purpose. To increase the efficiency of the technical operation of motor vehicles on the basis of the road method for diagnosing brake systems. Methodology or methodology for conducting work. The article considers the road method using accelerometers. Results. The main disadvantages of the road method and stands of various designs are considered, which give low reliability of the determined parameters of efficiency and stability during vehicle braking. The effectiveness of the implementation of on-line road diagnostics of automotive braking systems of multi-channel accelerometers is shown, which, when assessing course stability during braking, provide visually convincing information with a fairly high level of reliability. Practical implications: the results of the study can be used by car service organizations.

The article deals with the issues of modeling the stress-strain state of the attachment points of the cab of a wheeled chassis of high load capacity. The main design loads are determined. Geometric and computational finite element models are constructed, taking into account the features of the metal structure. The technique of gluing elements of the grid model is applied. The contact interaction of the parts is taken into account. Based on the calculations performed, conclusions are drawn about the compliance of the developed structure with the strength requirements.

The paper considers a method for calculation and evaluation of an automated brake proportioning system and it also describes assessment of efficiency while using cohesion forces of an automated system during vehicle braking process (MAZ 256200 taken as an example). A method for efficiency estimation of the vehicle braking equipped with an automated brake proportioning system is graphically presented in the paper. A comparable analysis has been made in order to evaluate vehicle braking efficiency in three various conditions of its wheel motion during braking process. The paper contains description of braking processes for a vehicle at its idealized braking, at braking with an operating automated system and at braking with blocked wheels. Mathematical dependences have been proposed and they make it possible to calculate a coefficient of cohesion forces used by an automated brake proportioning system on the basis of time parameters for vehicle braking process. The proposed mathematical dependences take into account design peculiarities of the automated system, i.e. a diagram of modulator arrangement on axes of the vehicle. The executed analysis for calculation accuracy of the coefficient pertaining to use of cohesion forces of the automated system with and without taking into accout rolling force resistance of the vehicle wheels has demonstrated a possibility to apply the proposed calculation methods for carrying out auto-technical expertise while investigating road-traffic accidents involving transport facilities equipped with such systems as ABS. The paper proposes a dependence for identification of a vehicle braking distance on the basis of the coefficient on use of cohesion forces by the automated brake proportioning system. The executed experimental investigations on both test and serial models of the automated brake proportioning system have allowed to justify theoretical discussions concerning application of tyre-road adhesion in the operational process of the vehicle brake proportioning system. The investigation results have shown high efficiency of the test automated brake proportioning system developed by Chair of Automobiles in the name of A. B. Hredescul at Kharkiv National Automobile and Road University under the following braking conditions: dry road surface and compacted snow cover.

The study has shown that the accuracy of brakes checking by inertial stands depends upon the applied methods of measurement of braking parameters (stand slowing down, braking distance, brakes triggering time, current speed) as well as the methods of metrological checking of measuring system canals.

It was developed a braking system for electric trains equipped with cast iron braking shoes, which allows shortening braking distance at emergency braking. Braking efficiency Increase is provided at the expense of braking force regulation depending on train speed according to calculated force of wheels with rails cohesion change. Analytical dependencies set as the basic of suggested braking model are given. It was made an analysis of ways of change of braking shoes pressing force at speed change. It is given the description of the working principle and operation of braking pressing rapid regulation. The offered braking system is being introduced at motor-carriage depot Minsk. Decrease of braking distance at emergency braking is 15-25 %.