Usefulness of Transonic Model Static Data in Predicting Flight Abrupt-Wng-Stall

Abstract

An approach is provided to answer the question of whether one can rely solely on static data taken during a transonic model test to provide the certainty needed that a new aircraft will or will not have abrupt wing stall (AWS) events during its flight operations. By the comparison of traditional static figures of merit (FOMs) with the free-to-roll (FTR) response data, a rational basis for assessing the merits of using standard testing techniques for the prediction of AWS events has been established. With use of the FTR response data as a standard, because these results compare well with flight, it is concluded that traditional FOMs can not be trusted to provide an indication as to whether a configuration will or will not have AWS tendencies. Even though these FOMs may flag features that have a high degree of correlation with the FTR response data, there are as many or more of these FOM flagged features that do not correlate. Thus, one needs to use the FTR rig to assess AWS tendencies on new configurations.