(b)
Table 1 and .gures 3 and 4 of this appendix must be used to determine values of n1, n2, n3, and n4, corresponding to the maximum design weights in the desired categories.
(c)
Figures 1 and 2 of this appendix must be used to determine values of n3 and n4 correspondingtotheminimum .ying weightsinthedesired categories,and,if these load factors are greater than the load factors at the design weight, the supporting structure for dead weight items must be substantiated for the resulting higher load factors.
(d)
Each speci.ed wing and tail loading is independent of the center of gravity range. The applicant, however, must select a c.g. range, and the basic fuselage structure must be investigated for the most adverse dead weight loading conditions for the
c.g. range selected.
(e)
The following loads and loading conditions are the minimums for which strength must be provided in the structure :
(1) Airplane equilibrium. The aerodynamic wing loads may be considered to act normal to the relative wind, and to have a magnitude of 1.05 times the air-plane normalloads(asdeterminedfromparagraphsA23.9(b) and(c) of this appendix) for the positive .ight conditions and a magnitude equal to the air-plane normal loads for the negative conditions. Each chordwise and normal component of this wing load must be considered.
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Elodie Roux. Septembre 2003
Appendix A : Simpli.ed Design Load Criteria
(2)
Minimum design airspeeds. The minimum design airspeeds may be chosen by the applicant exceptthat they may notbeless than the minimum speedsfound byusing.gure3 ofthisappendix.Inaddition, VCmin need not exceed values of 0.9VH actually obtained at sea level for the lowest design weight category for which certi.cation is desired. In computing these minimum design airspeeds, n1 may not be less than 3.8.
(3)
Flight load factor. The limit .ight load factors speci.ed in Table 1 of this appendix represent the ratio of the aerodynamicforce component(acting nor-mal to the assumed longitudinal axis of the airplane) to the weight of the airplane. A positive .ight load factor is an aerodynamic force acting upward, with respect to the airplane.
FAR 23.A9 : Flight conditions.
(a)
General.Eachdesign conditioninparagraphs(b) and(c) ofthis section mustbe used to assure su.cient strength for each condition of speed and load factor on or within the boundary of a V .n diagram for the airplane similar to the diagram in (Figure 35.6, p. 453)of this appendix. This diagram must also be used to determine the airplane structural operatinglimitations as speci.edinSecs.23.1501(c)through 23.1513 and 23.1519.
(b)
Symmetrical .ight conditions. The airplane must be designed for symmetrical .ight conditions as follows :
(1) Theairplanemustbedesignedforatleastthefourbasic.ightconditions, ”A”, ”D”, ”E”, and ”G” as noted on the .ight envelope of (Figure 35.6, p. 453) of this appendix. In addition, the following requirements apply :
(i)
The design limit .ight load factors corresponding to conditions ”D” and ”E” of (Figure 35.6, p. 453) must be at least as great as those speci.ed in (Table 35.1, p. 450) and (Figure 35.6, p. 453) of this Appendix, and the design speed for these conditions must be at least equal to the value of VD found from (Figure 35.5, p. 453) of this appendix.
(ii)
For conditions ”A” and ”G” of (Figure 35.6, p. 453), the load factors must correspond to those speci.ed in (Table 35.1, p. 450) of this Appendix, and the design speeds must be computed using these load factors with the maximum static lift coe.cient CNA determined by the applicant. Howe-ver, in the absence of more precise computations, these latter conditions may be based on a value of CNA = ±1.35 and the design speed for condi-tion ”A” may be less than VAmin.
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本文链接地址：FAA规章 美国联邦航空规章 Federal Aviation Regulations 3(8)
