The article considers the basic principles of designing and ensuring reliability of foreign manned spacecraft parachute systems. The operation algorithms of the parachute systems of American space descent vehicles are described. Using the method of block diagrams, the features of the constructing and functioning of the descent vehicle parachute systems of the "Gemini" and "Apollo" spacecraft, as well as the most modern ones, such as Crew Return Vehicle (CRV), "Orion" and "Manned Dragon" are analyzed. It is found that the design reliability of parachute systems of space descent vehicles should be at least 0.99996. It is determined that the service life and the number of applications of current space descent vehicles can be increased if designing the stability of any system to two joint failures is ensured. This principle of designing is being applied to aviation systems, is provided by their 3- and 4-fold redundancy, and it is used for the most important spacecraft systems. The reliability of modern parachute systems of the parafoil type has been studied

Landing parachute systems are among the most demanded samples of parachute equipment. The purpose of the study was to find new principles for developing parachutes with increased stability according to the analysis of the results of numerical and experimental studies of canopies of various shapes. The paper proposes to supplement a traditional definition of the stability of a parachute system with the obligatory consideration of the system’s ability to maintain a given trajectory of movement with a neutral canopy, regardless of the change in the payload mass. It is the expanded concept of stability that is taken as the basis of the modern approach to the design of foreign landing parachute systems. The study substantiates the main criteria for choosing the optimal cutting shape for parachute systems of increased stability of various types at the stage of preliminary design. The results of numerical modeling of canopies are presented: quarter-spherical, hemispherical, polyconic canopies and a T-11 type parachute canopy. Based on the analysis of these results, the study was first to propose a hypothesis that a decrease in the intensity of vortex formation in the wake leads to an increase in the stability of the parachute descent. The results of numerical modeling of canopies of various shapes, as well as experimental studies of a model polyconic parachute, which prove the correctness of the proposed hypothesis, are presented.

The paper analyzes various methods for determining forces during the opening of parachutes, based on the solution of a system of differential equations of motion of a mechanical system as a material point. The parachute inflation is a complex process in which the dynamics of air currents is closely related to the dynamics of the movement of the entire mechanical system: the payload, the parachute, and the involved air masses. The main problem in calculating the process of its inflation is that it is required to determine the maximum value of the loads during inflation, taking into account unknown parameters of the air mass mition directly near the parachute system and considering the implementation features of the design of parachutes. For the first time, a synthesized method for calculating loads when inflating parachutes is presented, considering the compliance of the structure, for which two methods were combined: (1) the existing one, to determine the reduced speed of the system when inflating the parachute, and (2) the new one, to determine the coefficient of parachute dynamism under conditions of “infinite” mass.

The development of parachute precision aerial delivery systems (PADS) has been going on since 1940s. Relying on the analysis of the aerodynamic characteristics of various gliding parachutes, the paper specifies the aerodynamic configuration for modern parachute precision aerial delivery systems, determines the types and considers the possibility of unifying the design of the main parachutes of such systems. The paper describes the history of gliding parachutes, summarizes the experience of developing such parachutes, and considers the evolution of maneuverable and steerable parachutes. In our study, we introduce and substantiate a new for the Russian practice classification of parachutes with aerodynamic quality. First, aerodynamic characteristics of various gliding parachutes were generalized and the main requirements for parachute PADS were indicated. Then, modern combined parachute PADS of Airbone Systems, USA, developed on the basis of double-surface parafoil parachutes were analyzed and classified with the emphasis on the types of modern systems. Since unification is most responsible for reducing the cost of industrial production of any technical systems, we considered the issues of possible unification of parachute PADS. Findings of research show that the unification of modern combined PADS depends on the common elements of control systems. It is worth noting that unification for systems of the ultralight class in terms of main parachutes is possible when using individual parachutes. For parachute systems of the middle and heavy class, intraspecific unification is possible through the use of single parachute modules.