Swarms of 3D printed drones may be the future of combat, according to a recent report by the Washington, D.C.-based defense think tank Center for a New American Security (CNAS).

3D printed drones would be cheaper and quicker to design, build and deploy than America's current manned aerial combat fleet, according to the report, titled "Process Over Platforms – A Paradigm Shift in Acquisition Through Advanced Manufacturing."

"Every year the U.S. Department of Defense (DOD) spends billions of dollars to develop and acquire weapons systems that ensure America's armed forces remain the best-equipped in the world," report authors Aaron Martin and Ben FitzGerald wrote. "The system for doing this is outdated, expensive, inflexible and slow."

Future battles may be decided by sheer numbers, as America's enemies are likely to amass drone fleets for the same reasons the report recommends we shift to robotic warfare with semiautonomous drones, according to the report.

"The current strategic decision to invest in smaller numbers of technologically superior aircraft may not hold valid in future scenarios where advanced enemies could field sophisticated UAS swarms or large numbers of manned aircraft," Martin and FitzGerald wrote.

The report notes 3D printing offers the DOD several important advantages over traditional manufacturing, like reduced assembly requirements, as components can be built into each other, fewer tools are needed and they can be redesigned and improved upon much easier.

3D printed drones can be made 24/7 on robotic assembly lines, can be created and deployed within weeks and can offer "operational flexibility for commanders as they weigh the risks of combat losses for some operations," the report states.

To drive home the point of how the current system is becoming increasingly obsolete, the report compares several key variables in the design and production of the F-4 Phantom II jetfighter, which was developed and acquired in the 1950s and 60s, and the brand new F-22 Raptor.

For instance, the F-4 took six years and $2.2 billion to develop, compared to the F-22s $39.3 billion and 22 years.

It took 14 months to build a single, $21.4 million F-4, while it currently takes 41 months to build one F-22 at a cost of $174.5 million each.

And in the end, 2,078 F-4s were delivered while only 187 F-22s are operational so far.

Ultimately the report states that change will be painful and there will be plenty of people with vested interests fighting to keep the status quo, but it also says America's current defense strategy is unsustainable.

"If the DOD and U.S. defense industry do not innovate boldly, others will," Martin and FitzGerald wrote in closing.