Radio altimeters are an important component of modern helicopter on-board systems. These devices currently involve the use of narrowband deterministic signals, that limits their potential technical characteristics. Given the significant breakthrough in the development of wideband and ultra-wideband radio electronics, it is promising to create on-board radio complexes capable of obtaining the necessary information using wideband stochastic signals. At the same time, when developing such complexes, it is important to use optimal synthesis methods for radio systems, which will allow optimal signal processing algorithms and potential accuracy parameters to be obtained. In this work, the algorithm to measure flight altitude for a helicopter or an unmanned aerial vehicle based on the processing of wideband and ultra-wideband pulsed stochastic signals is synthesized for the first time by the maximum-likelihood method. When formulating the problem, the mathematical model of the signal and observation is specified, and their statistical characteristics are investigated. The peculiarity of the synthesis task is the use of a noise pulse transmitter, which implements the function of an underlying surface illuminator, as well as considering the signal structure destruction during its radiation, propagation, and reflection. This signal shape destruction makes it impossible to synthesize a radar with internally coherent processing when working on one receiving antenna. In accordance with the synthesized algorithm, a simulation model of a pulsed radar with a stochastic probing signal has been developed and the results of its modeling are presented.

The method for determining the main parameters of the tail cargo doors of transport category aircrafts is developed. A methodology for the ascertainment of these parameters has been described. An example based on an existing transport aircraft is considered. Gathered were information pertaining to the necessary design, operational and regulatory parameters and requirements of the international regulatory organisations Federal Aviation Regulations (FAR), Certification Specification (CS) and Aviation Regulations (AR). The principle of determining the dimensions of the cargo compartment, cargo floor and the hitting platforms, in the form of a ramp with a pressure door and ladders, is presented based on the initial data. Considering the described loading and unloading, as well as landing, operations, the dependence of the ramp length on the length of the cargo floor is ascertained. A method for designing a cargo door fairings in the transport category aircraft fuselage tail part is presented. The main features of the fairings compartment have been determined, together with those of its main components and their varieties, depending on the scheme of the cargo door. Information is provided on the fairings compartment structural elements parameters selection.

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This paper present the results of our project to develop the preliminary design of a jet trainer plane (JTP) with a two-person crew, the base version of which is intended for cadet training. We first consider the assumptions and requirements for the new aircraft, and review the parameters of existing aircraft designs in the similarly-purposed class. Next we argue for certain design choices, regarding the aircraft layout, cockpit configuration, wing location and wingform, tail scheme, and powerplant. The resulting aircraft design is calculated to have a maximum flight speed of 940 km/h, a ground-level rate of climb of 100 m/s, and a range of 1130 km. The plane’s take-off mass is calculated, in three approximations, at 2264 kg. Lastly we present the training plane’s geometrical parameters, general view, and master geometry.

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