(a) If allowed by the specific requirements in this part, the values of control surface loading in this appendix may be used to determine the detailed rational requirements of §§ 23.397 through 23.459 unless the Administrator finds that these values result in unrealistic loads. (b) For a seaplane version of a landplane, the landplane wing loadings may be used to determine the limit maneuvering control surface loadings (in accordance with B23.11 and figure 1 of Appendix B) if— (1) The power of the seaplane engines does not exceed the power of the landplane engines; (2) The placard maneuver speed of the seaplane does not exceed the placard maneuver speed of the landplane; (3) The maximum weight of the seaplane does not exceed the maximum weight of the landplane by more than 10 percent; (4) The landplane service experience does not show any serious control-surface load problem; and (5) The landplane service experience is of sufficient scope to ascertain with reasonable accuracy that no serious control-surface load problem will develop on the seaplane. B23.11 Control surface loads. Acceptable values of limit average maneuvering control-surface loadings may be obtained from figure 1 of this Appendix in accordance with the following: (a) For horizontal tail surfaces (1) With the conditions in 23.423 (a). obtain w as a function of W/S and surface deflection, using (1) Curve C of figure 1 for a deflection of 10° or less; (11) Curve B of figure 1 for a deflection of 20°; (iii) Curve A for a deflection of 30° or more; (iv) Interpolation for all other deflections; and (v) The distribution of figure 7; and (2) With the conditions in § 23.423(b). obtain wo from Curve B of figure 1 using the distribution of figure 7. (b) For vertical tail surfaces (1) With the conditions in § 23.441 (a) (1). obtain w as a function of W/S and surface deflection using the same requirements as used in subdivisions (a) (1) (1) through (a) (1) (v) ; (2) With the conditions in § 23.441(a)(2). obtain w from Curve C, using the distribution of figure 6; and obtain w from Curve A, using the distri(8) With the conditions in § 23.441(a) (8), bution of figure 8. (c) For ailerons, obtain w from Curve B, acting in both the up and down directions, using the distribution of figure 9. 99-130-69-10 wwwwwwww.w 1.5 FIGURE 2-MANEUVERING TAIL LOAD INCREMENT (UP OR DOWN) FIGURE 3-Down Gust LOADING ON HORIZONTAL TAIL SURFACE NOTE (1). K may be determined as follows: K=0.25 for W=3,000 pounds or less; K=0.33 for W=6,000 pounds or greater, with linear variation of K between these weights. NOTE (2). For the purpose of design, the maximum load factor is assumed to occur throughout the shock absorber stroke from 25 percent deflection to 100 percent deflection unless otherwise shown and the load factor must be used with whatever shock absorber extension is most critical for each element of the landing gear. NOTE (3). Unbalanced moments must be balanced by a rational or conservative method. NOTE (4). L is defined in § 23.725(b). |