LATERAL-DIRECTIONAL OSCILLATORY-DEPARTURE CRITERIA FOR HIGH ANGLE-OF-ATTACK FLIGHT CONDITIONS

摘要

The present work deals with the problem of developing approximate analytical criteria for predicting departure from controlled flight of airplanes at high angles of attack. Specifically, the paper is concerned with the case of departure caused by oscillatory divergence of the lateral-directional perturbed motion. Unlike other scientific contributions, which relate departure phenomena to the occurrence of a Dutch roll divergence, this paper reveals the existence of a lateral-directional oscillatory-departure mechanism generated by the roll-spiral ("lateral phugoid") mode. By means of a relevant case study, it is shown that such a divergence can be predicted, with great accuracy, using a new approximate algebraic criterion.