When Martin Truex Jr. hung up his helmet after the 2024 NASCAR Cup Series season, many expected a part-time schedule or a turn to the broadcast booth. But few foresaw the 2017 Cup Series champion going into private aviation.Now retired from full-time racing, the 45-year-old has launched MTJ Aviation, a charter flight company with a lifesaving mission. An ARGUS Gold and WYVERN-certified Part 135 operator, the company handles critical medical flights. They specifically serve transplant centers across the US, offering 24/7 private medical transportation services without the bureaucracy of usual charter models.According to the company's website, it is a direct product of Truex's years of travel experience as a NASCAR driver:"I decided to launch a private aviation charter company because of our experience flying to NASCAR races every weekend over the last decade... MTJ Aviation offers a refreshing alternative... we simply fly you from point A to point B, safely at a reasonable cost."Martin Truex Jr. closed his full-time NASCAR career at the end of 2024, after two decades at the highest level of stock car racing. He clinched his lone Cup Series championship in 2017 with Furniture Row Racing. But after 2024, he chose to step away.He hasn't disappeared from the sport entirely and ran the 2025 Daytona 500 with TRICON Garage. But he's kept a notably low profile since, and there have been no further starts in Cup, Xfinity, or Trucks.(L-R) Helio Castroneves, Martin Truex Jr., and Jimmie Johnson before the Daytona 500. Source: ImagnEarlier this year, Truex listed his long-time home in Mooresville, North Carolina, a $7.5 million mansion he purchased in 2006, suggesting a gradual exit from NASCAR's epicenter and focusing on other ventures.His latest venture, MTJ Aviation, is unlike traditional charter services aimed at business travelers or luxury flyers. His primary clientele are medical teams and transplant patients who need rapid, safe, and discreet transport. The company has invested heavily in staffing, where pilots are handpicked and trained.MTJ Aviation's Chief Pilot, Guy Cooper, brings over 15 years of experience in corporate aviation, including time with Delta Private Jets. Director of Maintenance Ron Dietz II has spent more than 20 years in the field, maintaining airframes and power plants. It's a team assembled not for flash, but for reliability.While MTJ Aviation gains traction, the absence of Martin Truex Jr. has been felt in the NASCAR paddock. The Daytona 500 earlier this year was thought to be a potential springboard into a part-time slate in 2025. He had hinted at a potential return to the Xfinity Series, and there was buzz about additional Cup starts. But as of now, nothing has materialized.Hunting, fishing, and flying: Martin Truex Jr. on post-retirement lifeMartin Truex Jr before the Bluegreen Vacations 500. Source: ImagnWhen Martin Truex Jr. sat down with Dale Earnhardt Jr. on The Dale Jr. Download in July 2024, they discussed what comes next. For Truex Jr., the answer was more time outdoors, more time flying, and less time living life on a schedule.Truex has long been known for his love of hunting and fishing, and those passions now fill the calendar where race weekends once lived."First good weather we get in October, we're going. Those first couple cold days… that is the best time to be up there. So we'll keep the plane ready to go," he said on the podcast, referencing an annual hunting trip he and Dale Jr. take to Ohio. (45:24 onwards)It speaks to the lifestyle Truex is carving out for himself after his full-time tenure in the Cup Series ended.Each fall, Truex has followed a routine: hunting in Kansas before Phoenix, then heading to Missouri afterward to visit close friends. That stretch from October through November has become his favorite time of year. The delay in the 2024 Phoenix finale threw off the schedule, but Truex still found his time in the woods.Whether or not we see Martin Truex Jr. in a racecar again is still uncertain. But he's exactly where he wants to be.