Influence of the electromagnetic suspension system on the load of the transport aircraft main chassis rack during symmetrical landing

Abstract

The task of calculating external loads on an airplane and its structural elements is important for designing and manufacturing an aircraft, as well as for further testing of its strength. The solution of such task provides correct calculation of the aircraft strength. One of the most important elements of the aircraft, which requires a fairly accurate calculation of the strength, is the means of landing. Afterall, the planes suffer the greatest number of accidents and catastrophes during landing and takeoff.Chassis provide takeoff and landing of the aircraft, maneuvering while moving on the ground and the dynamic loads level reducing. The type of chassis, as a consequence of a possible depreciation system for each aircraft, is selected taking into account the features of its design and conditions in which the aircraft is operated.Currently, most aircraft use a passive hydraulic suspension. One of the main features of the hydraulic suspension is the use of hydraulic oil as a shock absorber. Whenever an aircraft crosses the inequalities on the runway, the surface excitation power is absorbed by the damper. The absorbed energy turns into heat inside the damper. However, there are some disadvantages of the hydraulic system.As a result of the carried out researches it is determined that at symmetrical landing the main chassis rack load of the transport aircraft and the maximum load arises from the horizontal load on the chassis rack in the case of landing on the dirt runway. The electromagnetic suspension system works well with peak and working loads due to its low response time and the absence of fading self-stabilizing oscillations of the system. The use of the electromagnetic suspension system allows fast and effective damping of the load perceived by the stable chassis at symmetrical landing, reducing the necessary mileage for braking, giving the pilot more time to analyze and assess the landing process and compensating for possible miscalculations when choosing the pitch angle at approaching the concrete runway