CS 25.471 General

(a)Loads and equilibrium. For limit ground loads –

(1)Limit ground loads obtained under this Subpart are considered to be external forces applied to the aeroplane structure; and

(2)In each specified ground load condition, the external loads must be placed in equilibrium with the linear and angular inertia loads in a rational or conservative manner.

(b)Critical centres of gravity. The critical centres of gravity within the range for which certification is requested must be selected so that the maximum design loads are obtained in each landing gear element. Fore and aft, vertical, and lateral aeroplane centres of gravity must be considered. Lateral displacements of the centre of gravity from the aeroplane centreline which would result in main gear loads not greater than 103% of the critical design load for symmetrical loading conditions may be selected without considering the effects of these lateral centre of gravity displacements on the loading of the main gear elements, or on the aeroplane structure provided –

(1)The lateral displacement of the centre of gravity results from random passenger or cargo disposition within the fuselage or from random unsymmetrical fuel loading or fuel usage; and

(2)Appropriate loading instructions for random disposable loads are included under the provisions of CS 25.1583(c)(1) to ensure that the lateral displacement of the centre of gravity is maintained within these limits.

(c)Landing gear dimension data. Figure 1 of Appendix A contains the basic landing gear dimension data.