The compressive buckling stress of outstanding flanges reinforced by bulbs was computed by the strain-energy method for flanges having 10 shapes and a range of lengths. The results were checked for some cases by computations based on a differential-quation method. The edge of the flange opposite the bulb was considered clamped, and the loaded ends were considered simply supported.

Time-history data of airspeed, altitude, and acceleration obtained with the NACA VGH recorder from a twin-engine airplane operated by a regional feeder airline in the Rocky Mountains are evaluated to determine the magnitude and frequency of occurrence of gusts and gust accelerations and the operating airspeeds and altitudes. The results obtained are compared with the results previously obtained from a representative short-haul and long-haul operation.