Interior transition layers in flight-path optimization

Interior transition layers occur in flight path optimization by singular perturbation methods whenever the reduced solution exhibits multiple branches. Although such phenomena occur in many problems, it has been little studied in the literature. In this paper, we consider interior transition layers in vertical-plan e climb path optimization. Our approach is to treat the interior layer associated with the transonic energy state discontinuity as two boundary layers, one in forward time and the other in backward time. The initial states of the two boundary layers are matched to give continuous composite solutions at the point of reduced solution discontinuity.