Inside the US secret hypersonic bomber: Project Mayhem

The engineering of next-gen weapons and defense systems is a science built around speed. In the ever-growing competition for the fastest missile, the US Air Force has come up with the Project Mayhem, a secret hypersonic bomber that would be an air-breathing Mach 10 ( 12,350 km/hr speed) replacement for the SR-71.

History of Hypersonic Plane

The idea of a hypersonic plane dates back to the Space Race, culminating in the North American X-15A-2 record-breaking Mach 6.7 flight in 1967.

Further aerospace advancements created mechanical wonders like the supersonic SR-71.

What is Project Mayhem?

It is an expendable hypersonic multi-mission ISR (intelligence, surveillance and reconnaissance) and strike program. 

The U.S. Air Force Research Laboratory has recently awarded a $334 million contract to several engineering companies, including Draper, to oversee the designs, prototypes and tests of Project Mayhem.

Project Mayhem will likely involve meticulously simulating hypersonic flight’s punishing conditions of heat and speed. Because of  unique operating environment and the necessity of precision-sensitive design, Project Mayhem is turning to model-based engineering (MBE) to digitally construct every system on the hypothetical plane.

How is it different?

The mighty bomber would have a few advantages over its missile-based adversaries, but the big one would be usability.

Where missiles like the Russia’s Kinzhal, Zircon, and China’s Dongfeng-17 are expensive (around $100 million) one-shots, a hypersonic plane traveling in excess of Mach 5—Project Mayhem would reportedly travel Mach 10 —could be refueled and used again, and again, and again.

Limitations of Project Mayhem

Project Mayhem would likely use a multi-cycle propulsion system, employing a jet engine to reach Mach 3 before transitioning to an air-breathing scramjet for hypersonic speeds.

But designing a reusable plane at such speeds comes with serious limitations.

At Mach 5 and beyond, things heat up pretty fast thanks to friction and air resistance, so any plane hoping to go that fast and survive the experience would need to be cloaked in advanced materials that haven’t even been invented yet.

None of this even touches on the fact that maneuverability at such speeds will also be a gargantuan engineering undertaking, and that combining a traditional jet engine with a scramjet has never been successfully accomplished.