Experiments on streamwise vortices in a swept wing boundary layer and their secondary instability Kozlov, V.V., Chernoray, V.G., Dovgal, A.V., Loefdahl, L. 2006 In Laminar-Turbulent Transition. Proc. of Sixth IUTAM Symposium, Bangalore, India 2004, 415–418, Dec. 13–17 (ed. Govindarajan R.), Springer A detailed experimental study on the formation of crossflow vortex mode packets and their secondary instability in a swept wing boundary layer was carried out. As a result, two modes of nonstationary perturbations traveling along the vortices were found.