Throughout aerospace history, production contracts for military aircraft programs have been awarded and then cancelled as political, technological, and operational dictates mandated. Many legendary airplanes like the Northrop YB-49 Flying Wing, the Canadian CF-105 Arrow, and the Mach 3 Lockheed YF-12 Interceptor were actually built and flown successfully before being cancelled. Others, such as the North American F-108 Rapier, never made it past the mock-up stage. This book shows, for the very first time, what might have happened had these cancelled designs, often fraught with corporate politics and industrial intrigue, actually entered production and operational service.