(b) Maneuvering envelope. Except where limited by maximum (static) lift coefficients, the airplane is assumed to be subjected to symmetrical maneuvers resulting in the following limit load factors:
(1) The positive maneuvering load factor specified in §23.337 at speeds up to V
(2) The negative maneuvering load factor specified in §23.337 at V
(3) Factors varying linearly with speed from the specified value at V
(c) Gust envelope. (1) The airplane is assumed to be subjected to symmetrical vertical gusts in level flight. The resulting limit load factors must correspond to the conditions determined as follows:
(i) Positive (up) and negative (down) gusts of 50 f.p.s. at V
(ii) Positive and negative gusts of 25 f.p.s. at V
(iii) In addition, for commuter category airplanes, positive (up) and negative (down) rough air gusts of 66 f.p.s. at VΒ must be considered at altitudes between sea level and 20,000 feet. The gust velocity may be reduced linearly from 66 f.p.s. at 20,000 feet to 38 f.p.s. at 50,000 feet.
(2) The following assumptions must be made:
(i) The shape of the gust is—
Where— s =Distance penetrated into gust (ft.); C =Mean geometric chord of wing (ft.); and Ude =Derived gust velocity referred to in subparagraph (1) of this section.
(ii) Gust load factors vary linearly with speed between V
(d) Flight envelope.
View or download PDF[Doc. No. 4080, 29 FR 17955, Dec. 18, 1964, as amended by Amdt. 23–7, 34 FR 13087, Aug. 13, 1969; Amdt. 23–34, 52 FR 1829, Jan. 15, 1987]
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