The REAL reason we don't have MACH 5 AIRPLANES yet

Added: 2026-06-07

[00:00:00]But believe it or not, as challenging as the aerodynamic and material sciences required to sustain speeds in excess of Mach 5 really can be, they haven't really been the limiting factor in making hypersonic aviation commercially viable. After all, the US already has a long history of controlled hypersonic flight to pull from, ranging from the affforementioned Mach 6.7 X-15 of the 1960s to the space shuttle that would regularly exceed Mach 25 after re-entry starting in 1981 through scramjet demonstrators that flew as fast as Mach 9.6 six in the early 2000s and right up through the Aremis 2 mission from a month ago that saw its Orion capsule reach Mach 32 after it re-entered the atmosphere. And firms like McDonald Douglas were filing patents on specific formulas for titanium alloys that could withstand repeated hypersonic temperatures as far back as 1989. That's all to say that while the science of hypersonic flight is very tough, it's not insurmountable. And the real barrier preventing it from becoming a reality really just comes down to a costbenefit analysis. Each and every one of the hypersonic platforms that I just listed a minute ago relied on a variety of other platforms along with rockets, many of which could not be reused just to get off the ground. And as you might imagine, if you need to involve heavy payload bombers and single-use rockets just to get your hypersonic aircraft into the air, well, it doesn't make for a very cost-effective way to do much other than gather scientific data or deliver a warhead, which is why most hypersonic platforms in development today are designed to do well, one of those two things.