Scariest environment you haven't written about yet... "The halls of Congress." - Jack Stewart

Jack Stewart spent 23 years landing fighter jets on aircraft carriers at night. He says landing on a carrier never really gets easy, and it never gets enjoyable either. That's the same discipline he brought into taking over Tom Clancy's Jack Ryan Jr. series. Instead of writing another cockpit story, Stewart sent his first outing 600 feet underwater instead.

The choice traces back to years after he left active duty, when he managed a dive operation for an undersea construction company. He watched deep sea divers up close and decided they were crazier than pilots. To write about them honestly, he went and got scuba certified himself, and came away with a fact that still surprises him: a diver 600 feet down is technically farther from breathable air than an astronaut on the space station.

Stewart also opens up about the people who shaped him. A wing commander once pointed him toward an open F-18 slot in the reserves, a conversation Stewart says changed the direction of his entire career. On the Rockin' 8, he tells the story of reenlisting a family friend as the man made master chief, the same person Stewart had sworn into the Navy years earlier as a young lieutenant.

He talks candidly about writing Master Diver Carla Bennett, a character built to make his lead cede control to someone else entirely, something Stewart says a lot of men in the military still struggle with. And he gets honest about writing inside a franchise this size. He still doesn't feel like he belongs in the same category as the writers who came before him in the Ryanverse, and says that discomfort is exactly what keeps his stories sharp.

Stewart also talks about restlessness. After 23 years of always chasing the next mission, he says he's still learning what it means to sit still. His go-to fix when a scene gets heavy is a playlist full of Sublime and Slightly Stupid, which he says keeps him calm enough to actually get the words out.

None of this happens without his family. He's been married 22 years, weathered deployments and airline schedules together, and now juggles book tours around flying full time for Southwest and visiting his sons at the Air Force Academy and Texas A&M.

Tom Clancy Pressure Depth is out now, wherever books are sold and at jackstewartbooks.com.