The fractional aircraft market is the fastest growing segment of the business aircraft industry. A fractional aircraft operation is complex - essentially an unscheduled airline in a constantly changing environment. Bombardier Flexjet implemented a comprehen- sive three-module optimization system to simultaneously maximize its use of aircraft, crews, and facilities. AD OPT Technologies designed the modules, using the GENCOL optimizer developed at GERAD, which employs a column generation approach to de- compose large-scale mixed-integer nonlinear programming problems. Since inception, the project has generated savings in excess of $54M with projected additional savings of $27M annually, primarily by substantially lowering crew levels (20 percent), aircraft inventory (40 percent), and supplemental charter aircraft usage (5 percent) while in- creasing aircraft utilization (10 percent). The quality of customer service has remained consistently high, with significant reduction in supply.