I’m sure you’ve seen it while hurtling down a highway in your car: a sign indicating that an airplane could monitor your speed. It seems silly; the idea that a “speed limit enforced by aircraft” sign could indicate the presence of a low-flying aircraft patiently waiting to ruin your day with a ticket. Well, it’s not as simple as a constant airborne police presence. 

What does speed enforced by aircraft mean?

Anytime a sign reads “speed limit enforced by aircraft,” law enforcement could use airborne means to communicate with ground units to uphold traffic laws. However, it doesn’t mean an action movie-esque maneuver wherein a helicopter lands to bust your wallet with a citation. 

Still, drivers who disregard the signage aren’t entirely off track; speed limit enforcement with aircraft was much more prominent 15 to 20 years ago, per KQED. Today, such measures are too expensive and impractical to justify use. Moreover, measures like Lidar (Light Detection and Ranging) are a much more accurate means of tracking vehicle speeds. 

How is the speed limit enforced by aircraft?

Agencies and law enforcement departments use markers to note distance and speed. Aircraft then communicate with ground units to target and pull over vehicles based on their speed over a certain distance. The concept isn’t unlike average speed cameras in the United Kingdom. 

However, in the case of several U.S. states, agencies may use helicopters or small fixed-wing aircraft to monitor speeds. Specifically, a spotter will accompany a pilot, monitoring the average speed of a vehicle over a section of road. 

How do you know if a speed limit is really enforced by aircraft?

In short, it’s unlikely that a speed limit zone you’re driving through is currently patrolled by aircraft. However, the California Highway Patrol (CHP) still operates small fixed-wing aircraft to aid ground units with information about a target vehicle, like make, model, age range, and color. 

Why do some states still allow departments to enforce speed limits with aircraft?

In short, there isn’t much to support the practice. Some states, like California and Illinois, may still fly a limited number of aircraft speed limit enforcement missions. However, it’s likely that the practice will continue to dwindle until it is all but extinct. 

Furthermore, disputing a ticket from an aircraft is just as possible as from a police car or on a motorcycle. As a result, the steep expense of running helicopters or fixed-wing aircraft for that purpose isn’t worth it.

However, with the advent of more advanced technology, like drones, airborne speed limit enforcement might wear a different face in the coming years. Keep up with MotorBiscuit for the latest news and content on everything from racing to safety!