Buzz
On your travels, you may spot signs along the road that read “speed limit enforced by aircraft.” These signs might make you imagine police pilots calling in a team of fighter jets to apprehend a speeding driver. In reality, the process is less dramatic than it seems.
Take Pennsylvania, for example. Specific sections of highway notorious for speeding are closely monitored by the State Police Aerial Reconnaissance Enforcement (SPARE); other states have their own variations of such programs. These sections of road are marked with designated start and finish points spaced apart. Two officers—a pilot and a spotter—monitor these stretches in a small fixed-wing aircraft (though some states may use helicopters).
As a vehicle crosses the start line, the spotter employs a specially designed stopwatch (some police forces also rely on VASCAR systems) to measure the car’s speed within the enforcement area. If the vehicle is speeding, the officers in the plane radio a ground officer to pull the car over and issue a citation.
Monitoring speeders from the air is less frequent than it used to be, due to advancements in technology like radar and Lidar. Budget reductions have also impacted this method. “We don't necessarily conduct as many dedicated speed enforcement operations as we did 10 or 15 years ago, mainly because of the advent of Lidar,” Jim Andrews, a pilot with the California Highway Patrol, told KQED. “However, there are still situations where we are definitely useful, especially when traditional ground enforcement isn’t effective.”
A number of states have drastically scaled back or practically abandoned their aerial enforcement programs. But that doesn’t mean you can disregard those “speed limit enforced by aircraft” signs when you pass by. Depending on the state you're in, there's still a possibility that someone could be monitoring your speed from above.
