Raytheon and Northrop Grumman are developing 3D printed engines for smaller hypersonic missiles that could be deployed in at lower cost in swarms. The air-breathing scramjet will use regular aviation fuel. Northrop Grumman has new materials and technology to 3-D print the entire engine (the combustor).
3D Printing will make construction faster and significantly less expensive manufacturing. The weapon has completed ground testing and will fly soon.
The vision is to make swarms of up to 30 hypersonic scramjets the size of cruise missiles, launched from air, land and sea. The missiles will share data with each other, correcting their flights, perhaps changing targets midcourse. And they can be manufactured relatively quickly and for much less cost than most of the hypersonic vehicles that have been built so far.
Northrop Grumman and Raytheon are working under a $200 million Hypersonic Air-breathing Weapon Concept, or HAWC, program contract to deliver an affordable, effective and producible cruise missile for DARPA and the U.S. Air Force.