Down Gusts: An Examination of the Down Gust Structural Strength Requirement at Lightly Loaded Weight

Abstract

IT is shown that the down gust requirement is open to the objection that heavier loads may be taken by the front spar at lightly loaded weight than those for which the spar was designed. This is normally covered by the factor of safety of 2, but the method of calculating the loads on a basis of all up weight is not very rational. Some available data concerning the magnitudes of down gusts are reviewed and the sharp‐edged gust hypothesis briefly examined. The British requirement is compared with those of the I.C.A.N. and the U.S.A. The conclusions are that there are no very practical alternatives to sharp edged theory and while the estimate of the magnitudes of normal down gusts at 25 f.p.s. appears satisfactory and British standards of strength in this respect need not be tightened up, a modification to the requirement to meet the above objection is desirable. A suggested alternative is put forward.

Citation

Crowe, J.H. (1937), "Down Gusts: An Examination of the Down Gust Structural Strength Requirement at Lightly Loaded Weight", Aircraft Engineering and Aerospace Technology, Vol. 9 No. 5, pp. 119-122. https://doi.org/10.1108/eb030177