1. A method of generating linear models for an aircraft engine system, the method comprising: determining, offline, a set of linear models for the aircraft engine system by linearization of a nonlinear model of the aircraft engine system at selected operating points or from desired data; analyzing, offline, accuracy of each linear model and eliminating inaccurate linear models therefrom to provide a residual set of the linear engine models; generating, offline, linear models corresponding to grid points of one or more rectangular lookup tables based on the residual set of the linear engine models; associating, offline, lookup table grid points or the residual set of the linear engine models with selected scheduling variables; and generating, offline, algorithmic software for the aircraft engine system therefrom such that the linear models for the aircraft engine system generated offline form a basis for online scheduling of linear models.