Gust and turbulence loads.

CFR · 2024-01-01 · US · Title 14

(a) (1) Loads on each part of the structure must be determined by dynamic analysis. The analysis must take into account unsteady aerodynamic characteristics and all significant structural degrees of freedom including rigid body motions. (2) The shape of the gust must be: (3) A sufficient number of gust gradient distances in the range 30 feet to 350 feet must be investigated to find the critical response for each load quantity. (4) The design gust velocity must be: (5) The following reference gust velocities apply: (i) At airplane speeds between V (ii) At the airplane design speed V (6) The flight profile alleviation factor, F (7) When a stability augmentation system is included in the analysis, the effect of any significant system nonlinearities should be accounted for when deriving limit loads from limit gust conditions. (b) (1) Except as provided in paragraphs (b)(4) and (5) of this section, the following equation must be used: (2) Values of (3) The limit turbulence intensities, U (i) At airplane speeds between V (ii) At speed V (iii) At speeds between V (iv) At all speeds, both positive and negative incremental loads due to continuous turbulence must be considered. (4) When an automatic system affecting the dynamic response of the airplane is included in the analysis, the effects of system non-linearities on loads at the limit load level must be taken into account in a realistic or conservative manner. (5) If necessary for the assessment of loads on airplanes with signific

official document · source cfr-2024 · id 14:§ 25.341