When I ask Bradley Worthington to tell me about that one time people in the southwest thought his trucking company, McCollister's, was moving a UFO across the country, he laughs. There’s not a “that one time.” “It happens frequently,” he says, “especially with oversized things.”

And McCollister's hauls a lot of oversized things. From astronaut capsules to weather-monitoring satellites to military aircraft, the company specializes in moving beefy, sensitive objects around securely. They've transported part of Orion, NASA's next astronaut-carrying spacecraft, and the recently-launched Joint Polar Satellite System-1, an environmental-monitoring system.

Worthington does, though, know the one time I'm talking about. It was when his driver transported an F-35 jet model from California to Texas. The big-rig took a break in southern New Mexico, where passersby saw it carrying a saucer-looking craft covered in a metallic shroud—which, when illuminated, beamed like something otherworldly. "It looked spaceship-ish," Worthington concedes, especially in a landscape long home to classified aerospace tests and undisclosed military experiments. “Everybody’s got their ideas,” Worthington says. “And if you stop for any reason, people want to know which UFO you’re transporting.”

Their confusion makes sense, in a way. "You don’t get a chance that often to see things going down the highway that aren't farm equipment or wind turbines," says Worthington. But that's exactly the business McCollister's is in. Satellites, rockets, and jets don't always lift off from the same places where they were built. And when it's time to make that big move, McCollister's big-rigs are here to help.

Worthington worked for Lockheed Martin for 35 years, in its space systems division. In 1995, he took over the transportation group, sometimes employing McCollister's to move its precious cargo. Companies like Landstar, Bennett Motor Express, and VIP Transport also offer aerospace-shipping services. But when Worthington retired from Lockheed in 2016, he agreed to become vice president of McCollister's aerospace and defense arm.

The company actually started its high-tech transportation in the '70s with supercomputers—big IBM racks. But at an aerospace trade show in the '90s, an industry insider came up to McCollister's booth and described a "mishap with a transportation event." The guy's (classified!) cargo was in the back of a truck when the connection between tractor and trailer failed, shaking up sensitive equipment. McCollister's team started looking into how to mistake-proof that connection point: kingpins that lock, connections that rely on sliding bars or clamp down with metal jaws.

Decades later, McCollister's agents have gained a reputation for not dropping or shaking stuff that's spent years in development—like NASA's Orion crew capsule. In 2016, soon after Worthington started his new gig, McCollister's was tasked with moving part of the structure from Southern California to Colorado. Orion wasn't just an oversized load: It was a "super load", at 19 feet wide (your car, in case you haven't measured it lately, is likely around six feet wide).

Whenever you're moving something that is that big and that touchy, there's a lot to consider: the spacecraft's shape, how hot and cold and humid the air is, how much vibration is happening. And once a wide load like Orion gets on the road, the driver can't just toodle around, stopping at diners and "world's largest" food statues. Every state such a truck passes through requires a permit, and a route planner determines which roads have overpasses too low or lanes too narrow. For super loads, an actual human surveys the route. If anything about the cargo is classified, the company taps drivers with security clearance, of which McCollister's has 12.