МЕТОД ВИЗНАЧЕННЯ ОСНОВНИХ ПАРАМЕТРІВ ВАНТАЖНОГО ЛЮКА В ХВОСТОВІЙ ЧАСТИНІ ФЮЗЕЛЯЖУ ЛІТАКІВ ТРАНСПОРТНОЇ КАТЕГОРІЇ

Abstract

A method has been developed for determining principal parameters for aft cargo door of transport aircraft. A list of input data is given and a technique for finding them is described. An example based on an existing transport aircraft is considered. The following has been used as source data: basic cargo nomenclature to be transported by the designed aircraft, cargo overall dimensions and weight, methods of loading and mooring, loading facilities. More over the design, operational and regulatory parameters are needed, such as landing gear configuration, its bottoming system, extension of rails of the upper equipment for loading/unloading, cargo trajectories during loading and airdropping, codes of the international regulatory bodies such as FAR, CS, AP. Based on the source data, the principle of determining the dimensions of the cargo compartment, cargo floor and the loading sites in the form of a ramp with a pressure bridge, and air stairs is given. The relation between the ramp length and the cargo floor length is described taking into account the loading, unloading and air dropping operations. Correct calculation of these parameters is the most important task, because performance of the future transport aircraft directly depends on the solution. The technique of determining the cargo door opening, development of the load-bearing structure of the transport aircraft fuselage aft section, its main strong elements – the cargo door beam, the ramp, the attachment units, the ramp locks – is given. The interconnection of the ramp load-bearing structure with the load-bearing structure of the fuselage aft part, the options for transferring loads perceived by the ramp to the frame are described. Examples of two types – flat and volumetric – of the cargo door beams, as well as the method of their assignment are considered. Trajectories of the extreme points of the in-gauge load are determined using graphical method for loading, unloading, and airdropping operations. Taking into account the positions of these trajectories makes it possible to select the desired cutout in the fuselage aft section. While designing the aft cargo doors the main features are highlighted. These features when considered make it possible to determine the most optimal parameters of the cutout, the cargo door type and its components.