I don’t have any links, but there used to be occasional signs on the side of the road, indicating that this stretch was patrolled by aircraft. The signs were in a section that had the big white paint spots.
Either they really were catching speeders that way, or the troopers were convincing people that was what was happening, and getting drivers to slow down based on an assumption.
I’ve been stopped by cop cars that were black and white but had no gumball machine on top, so I couldn’t tell they were caps behind me.
They just said they held a steady pace at the speed limit and I pulled away from them.
No radar.
Once, on the Pennsylvania Turnpike, they stopped me at the toll booth and said my ticket time from the last booth proved I had speeded. Had to pay the fine right there since I was out of state.
“Speed monitored by aircraft” is usually intended as a sort of passive enforcement effort.
Usually these signs are adjacent to small airports, or at mountain passes, where there will be a good chance of low altitude aircraft traffic. They are technically correct, the aircraft pilots do monitor their own airspeed.
Using an aircraft, while occasionally done, is NOT a cost effective way to enforce speed limits: It requires an expensive to operate aircraft, a pilot, and an observer/stopwatch operator, and at least one officer on the ground. It is also tricky to clock more than one vehicle through the trap at a time. Only roads that have lots of violators per hour can justify the expense.
It also creates a problem in that the officer who signs your ticket is usually affirming that he personally witnessed the violation, which is NOT the case, and if such “shoot and loot” tickets are taken to court will be thrown out in some juristictions. If not, then at least two officers will need to appear in court, because neither of them alone can testify that it was actually you, and you were speeding.
I can back up our friend Tastes on the Iowa Bear in the Air system. The pilot- State Trooper generally just works one part of the state and actually paints the marks or the highway, or at least is physically present while department of highway guys do it. The marks change from year to year – some years it’s a circle, some years it’s a hashmark, some years it’s a little airplane painted on the blacktop. Usually the Bear in the Air works with a squad of Troopers and Deputies, radioing the description and license number of speeders ahead to the ground units at a road block some miles ahead. It doesn’t happen very often but when it does there are a batch of tickets written.