The freewheel is a universal subassembly, which is of great importance, for example, in the industry as a safety element (backstop), in the automobile sector as a coupling element or in aviation as a switching element between engine and main transmission. The main advantage of the directional clutch is the automatic clutch operation. The process is dependent on the currently available speed ratio from drive to output and is divided into the processes of overtaking and locking. The aim of this thesis is to elaborate the fundamentals of direction-dependent couplings, or also as free-wheeling, and provide an overview of the free-fall mechanisms currently established on the market. In the end, an outlook on possible further research and development targets is to be given on the basis of flight accident reports. To begin with the first part, the assembly is freely defined, as such, in the various normative rules. The operation and operating conditions are explained in more detail below. The main points in this section concern are the design and construction of sprag clutches. In doing so, the mechanical principles and the calculation algorithms which have developed over the course of time are discussed in detail. Furthermore, possible adaptations, in the form of springs and cages, are also explained in more detail. The second focus of this work is the evaluation of helicopter flight accident reports. In order to be able to classify these assessments, a catalog of criteria was drawn up on the basis of the reports, which is divided into five categories. Ascending with the lowest, in which the free-fall was not damaged, the assembly in the highest level has been the main reason for the crash of the helicopter. The conclusion of this chapter is a pool of possible approaches to make the assembly safer and therefore better understood.