(NEXSTAR) – You probably grew up spotting the signs from the backseat of your car on family road trips: “Speed enforced by aircraft.” As a kid, the idea may have sounded high-tech and intimidating. As an adult, it probably seems more costly and impractical. So do the patrols still happen?

The short answer is yes, some units across the country say they still patrol by aircraft, but technological improvements and cost considerations have limited air enforcement.

The California Highway Patrol recently explained how their unit works, in an effort to dispel anyone who may have thought a helicopter was about to touch down on the highway next to them.

“CHP fixed-wing airplanes will partner with CHP ground units. Several patrol cars will be staged at a specific location along the right-hand shoulder of the freeway waiting for communication from CHP Air. The aircraft uses markings along the right-hand shoulder to mark and measure distance. After factoring in a math equation, which determines the speed of the targeted vehicle, CHP Air communicates with the patrol cars on the ground,” CHP Stockton wrote. “The Air Unit will communicate to the ground units the targeted vehicle’s color, make, model and lane position, so ground units pull over the correct vehicle.”

In other places, a helicopter is deployed to hover over the aerial enforcement zone. Often the aircraft is staffed by a pilot and a spotter doing the ground speed monitoring, Cheddar explained in a 2022 video. This means a speed patrol typically requires a minimum of three officers, as well as the operational costs of all vehicles.

For many departments across the country, that overhead has proven too steep, and patrols have been trimmed back or even eliminated. An NBC affiliate in New York was told last year that the Empire State hadn’t conducted an aerial patrol since the 1990s, yet warning signs remained throughout the state.

On the flip side, the Akron Beacon Journal reported last year on investments in new technology, allowing the Ohio State Highway Patrol to expand aerial enforcement capabilities. So to a large degree, the risk of an airborne ticket depends on where you are driving.

In California, the threat of a ticket from an aerial speed patrol has dropped.

“We don’t necessarily set up as many specific speed enforcement details as we did 10 or 15 years ago, predominantly because of the advent of Lidar,” CHP Pilot Jim Andrews told KQED during a 2016 interview.

Lidar is a way of measuring a vehicle’s speed using laser light pulses. Police now use these devices commonly on speed patrols.

We reached out to the CHP Valley Division multiple times in an effort to get an update on how frequently the speed-specific patrols take place but did not hear back.

Still, aerial units may be deployed for other uses, and as the KQED piece points out, speeding and other traffic violations stand out quickly from above. You could get popped for a ticket even if the flight wasn’t launched just to catch speeders.