THE concept of a “sharp-edged” gust in which the wing is assumed to obey the laws of steady flow has proved useful as a temporary expedient in setting up design criteria for gust loads. However, the trend toward construction of large, heavily loaded transport airplanes and the problem of the light airplane require further rationalization of these criteria.
Present indications of extensive acceleration data obtained on the relatively small transports of the domestic airlines and on the large Clippers of the Pan American Pacific and Caribbean routes harmonize with theoretical indications that current design criteria are under-conservative for heavily loaded airplanes and over-conservative for lightly loaded ones. Occasional records of acceleration in very strong gusts, such as occur in line squalls, emphasize the necessity for avoiding severe weather conditions.