To further explore this topic, I’m using a fictional design of my own based on a not so fictional aircraft (or actually, an aircraft shrouded in mystery) known as the SR-91 Aurora. Rumoured to have been developed in the 1980s or 1990s, the SR-91 “Aurora” is purported to be a Mach 4+ hypersonic, clandestine, high-altitude Intelligence, Surveillance, and Reconnaissance (ISR) aircraft for the United States. However, other than a few interesting snippets of information, there is no direct evidence of the project’s true status, or that it even exists at all. So I took the liberty to use a fictional hypersonic NGAD-fighter and dubbed it: the YF-51 Aurora.