I used to live in a remote mountain village, located on one of the main highways across our central mountain range. 8km or so of the highway leading into the village was narrow and winding with no shoulder - the road lines were cut in the horse and coach days, so not designed for cars. It was surrounded by forest, often with bluffs on one side and a 20m drop on the other.

People crossing the centre line on blind corners because they were driving too fast were a real hazard on that section of road.

One summer (when the road was busiest) the Police ran an operation where a helicopter observed the road, and identified vehicles cutting corners, who were then pulled over outside the 8km stretch where it was safe to do so by waiting patrol cars.

They only ran it for a couple of weeks, but the calming effect of it on bad driving on that stretch lasted months, it was awesome.

So the Cessna might not be about making money, and more about the potential presence of the Cessna changing driving patterns increasing safety.

Even if they don't generate money from that, catching people speeding is a public service. If one disagrees with the idea that speeding is bad, then why don't we raise speed limits until the speeds deemed "reasonable" at under the limit.

They usually fly something like a 206 or 182 with a Flir gimbal and two people on board. Those types cost between $120 and $200 an hour to operate plus whatever the costs of the gimbal are (mind that the gimbal may cost as much or more than the host aircraft).

The pilot and sensor operator are paid so that's another $100+/hr after benefits and such are paid.

I'm guessing they just do it to subsidize the aircraft and give it something to do between calls when it's on station. The aircraft costs money just sitting in the hangar so it'll help justify the costs.

The one place I've seen a Cessna on speeder patrol it certainly paid for itself. There was a spot where an interstate cut through an Indian reservation. The speed limit was set to 65 mph even though the road was better than that.

A bird in the sky plus more cops than I would have thought they had were a frequent occurrence there, pulling over basically everyone who wasn't aware of the speed trap. Certainly worth it.

One day they raised the limit to 75 which is far more appropriate--I've never seen the plane since, I've seen one cop a couple of times hiding behind the crest of a hill.

What’s the ROI on responding to domestic disturbances in low income neighborhoods?

What a silly way to look at safety money.

Aren’t speeding tickets known to be really big income for local governments?

They can be hundreds of dollars; I’m sure it can work out financially if they can hand out enough, which seems likely from an airplane.

If they use those planes for other reasons (search and rescue, fire, etc.) then the cost is minimal. If the pilot weren't out there catching speeders he would be doing touch-n-goes, etc. to maintain currency.

Pilots have a minimum number of hours / approaches per time period, and planes have high fixed operating costs (annual service, hanger, etc.), combined the marginal cost of catching speeders is low.