The next time you fly into Florida's Fort Lauderdale airport, look out the window and see if you can spot what's missing. The answer? A 160 feet high tower.

That’s what airport officials at the airport say would have been necessary for them to be able to safely control the movement of planes on the ground, taxiing to and from gates and runways at the recently expanded airport. That would be doing things the old fashioned way, by line-of-sight—aka looking at the planes. Instead of an elevated perch, ground controllers at FLL have an even better view from inside a nearby squat, building.

“They have no windows in their building,” says Mike Nonnemacher, the chief operating officer for Broward Country Aviation Department, which controls FLL airport. “It’s all done by radar, and augmented by a system of CCTV and infrared cameras.” A new computer system takes the data from those cameras, and other sensors, and stitches it together into one giant virtual vista.

Controllers sit in front of a video wall, which shows them what’s happening in real time. The infrared images offer improved visibility at night and in the fog. Wearing headsets, they calmly issue cryptic sounding instructions to pilots, and then track the plane moving. It’s the first of its kind in the US, and could set the bar for other airports around the country.

Gregory Meyer/Broward County Aviation Department

In the US, the FAA runs air traffic control, which sees planes safely onto the tarmac. But responsibility for moving these huge machines around on the ground falls on the airport or airline. Their wingspans, which look so elegant in the air, are just a protruding hazard on the ground. Pilots don’t have great visibility out of the cockpit windows, so they rely on ground controllers to tell them which gate to taxi to, where to hold, which path to take, and to warn them of other vehicles like fueling trucks or passenger busses crossing active taxiways. It’s a complicated dance, becoming ever more so as air travel booms and airports expand, allowing takeoffs and landings with barely 30 seconds between them. Airfields usually have one or more towers, so ground controllers can see everything that happens from the runways to the gates.

The layout of the Fort Lauderdale airport makes it a great test case for something new. One row of gates is hidden from direct view of ground controllers, so they used to send someone on foot to scout the scene, report back, and help them keep track of aircraft on a dry-erase board. Tired of all the back and forth and eager to avoid the cost of building a looming tower, they went the virtual route.