Two elastic finite-element models of the thoracic system are presented to analyze the effect of imposed loads. A flexural model for the cartilage is derived to account for the significant difference between its tension and compression moduli. The two structural models studied are: first, the thoracic cage (skeleton) by itself, and second, the thoracic body including the cage, the muscles and the internal parts. The ribs, cartilages, sternum, vertebrae, intervertebral discs, muscles, and gross lung and heart organs are modelled by various types of finite elements, viz. beams, plates, membranes and solids. Eleven static and two dynamic loading cases are considered and the stresses and displacements under each loading are calculated. Comparisons are made between the skeletal model and the whole thorax model. This paper presents the static loadings as the first part of the development. The dynamic effects of the thoracic body by various types of finite elements will be considered in the second part to be presented separately.