Abstract: Skid landing gear provided with components having a device for absorbing energy by plastic deformation and/or for limiting stress, and components of this type.According to the invention, each of two undercarriage parts comprises a skid 170 connected to the structure to two crosspieces 175 and 176 that are hinged on the structure about an axis parallel to the hinge axis on the structure of the other crosspiece of the same undercarriage part, and at least one component 181 that has a main mechanical and/or hydraulic function, such as a strut, a cross-bracing or control jack, a shock absorber or a shock absorber jack, the component being provided with a device for absorbing energy by plastic deformation and/or for limiting stress, and is connected on the one hand to a crosspiece 176 of the respective undercarriage part and on the other hand either to the corresponding skid 170 or to the structure of the aerodyne.The invention is especially suited to use on helicopters.

Abstract: A structural support comprises inner and outer elements which are telescopingly engaged, a cage secured to the inner element and having apertures in which balls are disposed which are disposed radially between the two elements, and a frangible connection securing the two elements against relative axial movement. In the locked relative positions of the elements, the outer element has locally an increased internal diameter portion and the balls are radially disposed in this position or are moved into the portion on being subjected to an axial force which breaks the frangible connection, so that the relative axial movement of the elements results in the ball plastically deforming the outer element and absorbing energy from the force to protect the body carried by the support. The support can be used to provide a brace operating as a strut and/or a tie, or a shock absorber, or, by mounting a damping piston slidably in the inner tubular element can provide a shock absorbing piston and cylinder unit.