For the Pentagon, widespread adoption of digital engineering remains in progress


Hegseth, in confirmation hearing, signaled the transformation will be a priority

The B-21 Raider looks like a cross between an airplane and an alien spacecraft. Maybe that’s fitting for the U.S. Air Force’s next stealth bomber, built to evade detection and designed through digital engineering — that is, engineers developed the bomber with computer models, and analyzed and tested its capabilities in simulations before the B-21 ever took flight. As of late 2024, three prototypes were in testing.

“The handling qualities are better than expected coming out of the simulated environment – validating the accuracy of the digital models the team has analyzed over many years,” said Chris “Hoss” Moss, a B-21 test pilot, according to a September press release from Northrop Grumman, the B-21 prime contractor.

The Defense Department has wanted to see the successful application of digital engineering in the rest of its modernization efforts, from intercontinental ballistic missiles to combat vehicles. The first Trump administration introduced its digital engineering vision in 2018. The Biden administration expanded on this in 2023 with its own policy for implementing and utilizing digital engineering in defense systems.

This slow transition might be what Pete Hegseth was referring to during his Jan. 14 confirmation hearing to become secretary of defense. “The Pentagon often builds entire systems without first using a digital design, which means you build prototypes and then scrap them and start over again,” Hegseth testified.

If Hegseth, who was confirmed by the Senate on Jan. 24, meant that the digital transition remains a work in progress, he was right. The people creating today’s — and many of yesterday’s — weapons use computer-aided design, but such software is just one small piece of the Pentagon’s digital engineering strategy designed to “modernize our defense systems and prioritize speed of delivery to be able to fight and win the wars of the future,” according to a Pentagon memo announcing the Digital Engineering Strategy in 2018.

Digital engineering is a big umbrella that includes modeling and simulation. It often involves “digital twins,” a digital version of, say, a stealth bomber that engineers can test for how it might respond to stresses — heat, wind — in the real world.

Fully embracing digital engineering is more challenging than it might sound. Today, given the complexity of modern aircraft, different teams often work on different components, each tinkering with its own part, often with its own modeling and simulation tools.

“What happens is that often these tribes have to do rework because of decisions that the other tribes have made that impacts their work,” says Dinesh Verma, the director of the Systems Engineering Research Center (SERC), a university organization affiliated with the Department of Defense.

Digital engineering seeks to eliminate that separation, so if one team makes a change, it updates the entire model, and other teams can see how it affects their design. “I can have a near real-time sync up,” Verma adds. “If one tribe makes a decision, I can assess the impact of that on my tribe, for example, rather quickly.”

Google Docs, but for the next-generation warplane.

David Long, an independent expert on model-based systems engineering, describes the optimal digital approach like this: “We’ve got this very seamless connected flow,” he says. “So one: We don’t inject errors by reinterpreting things all the time and just manually translating data. But also, we can be far more collaborative and far more rapid.”

Researchers and industry leaders, including many with experience inside the military, say the Pentagon is moving in the right direction, but hasn’t figured out how to fully integrate or make digital engineering work throughout the department. Experts, industry insiders, and former military and defense officials said the Pentagon and its contractors and subcontractors still need more investments and coordination, including on security and a workforce steeped in how to use the tools.

The strategy also demands cultural and policy changes, including those governing how the Pentagon does acquisitions. “We have adversaries now that can innovate faster than the U.S.,” says Steve Bleymaier, a retired Air Force brigadier general and now chief technology officer of aerospace and defense for Ansys, a firm headquartered in Pennsylvania that develops simulation software. “They can produce weapon systems faster than the U.S. because we are still stuck with the system we have.”

That may be contracting language, federal regulations, or the entire budgeting system. “That process that we have that bogs everything down,” adds Bleymaier.

In addition to engineering, digital tools could generate real-time data on cost and supply chain logistics, which could reduce some delays and cost overruns now notorious in major defense acquisitions. This, the thinking goes, would also help the Pentagon better assess its warfighting capabilities: What it has in its arsenal and what it wants to have. And then respond by modernizing old programs or accelerating new ones based on current threats.

“It allows a better articulation and a better understanding of where the challenges are and where the benefits are to the warfighter and to the inventory as a whole,” says Philomena Zimmerman, a research scientist who has spent her career working on digital engineering for the Department of Defense, including helping to shape the 2018 strategy.

At the same time, there is a risk of putting too much faith in digital engineering. “It’s not right now the panacea,” says Obaid Younossi, a RAND senior policy researcher. The U.S. is building ever more advanced and complex weapons, and these still require real-life tests because they are as yet untried in battle. People still need to build and test physical prototypes.

“The more complicated something gets, it is harder to address all of it digitally,” Younossi says.

If the B-21 Raider is a model for digital engineering, then ground and flight tests will prove it.

For the Pentagon, widespread adoption of digital engineering remains in progress