Critical gust

Abstract

The purpose of this analysis is to present a new, simple, and approximate method of calculating the characteristics of the critical graded gust, as a function of physical characteristics of the aeroplane under study. The effect of this gust on the normal load factor, and design requirements for wing flexibility are also presented. This study has made it evident that it is illogical to fix the magnitude of the design gust velocity as proposed in some present day airworthiness requirements (e. g. U ~ 10 m/sec; H ~ 30 m). Likewise, the standardization of distance H is illogical for the determination of structural flexibility criteria. This paper then, makes the first attempt to establish values of critical U and H dependent on the characteristics of the particular aeroplane under study. The seriousness of wing flexibility in high performance sailplanes was emphasized and covered an equation. This equation may not be strictly applicable to heavily loaded aeroplanes.  The relationship given in another equation is perhaps modified for this type of aeroplane.