Engineer uses tape measure to beat speeding ticket

The line was only off by 3 inches. Yes that is wrong but I doubt enough to really matter.

It was the space between the lines that was off. If the space between the lines was less than it should be then it would appear a vehicle was traveling faster than the actual speed as it would take less time to travel the correct distance.

This is the same process VASCAR uses to measure speed, the amount of time it takes to travel a specific distance equates to the speed the vehicle is apparently traveling.

technique is used here in the US in some states, ever notice white lines on some of the inter-states? they use aircraft to time cars from one line to the next and I don't believe the lines are a mile apart, I think they are usually 1/8th of a mile and the time multiplied by 8 to get the mile time.

Actually, it's 1/4 mile and they don't multiply anything. Standard tables will tell you the speed for the time over the distance.

The speed cameras in the USA use radar and the lines have nothing to do with the speed.
The only way you can beat the system is if you get caught and when they show you the photos calculate the distance you traveled between the photos and compare the time stamps with your own calculated speed.
For fun I took Google Earth and with the measurement tool I found out that on two different interstates the lines differed by as much as one foot in side by side lanes. They are painted by a truck driving down the road at a certain speed and with preset distance will turn on and off the sprayer. Not all trucks are equally accurately set with precision.

this guy is my hero, what a studd!

Don't know what lines you are talking about, but there are still places in the US where lines across the road are painted specifically for airplane speed enforcement use. They span the full road width, and don't look like part of the standard painting at all.

Quite possibly you don't see them where you drive, but they do exist.

They exist but have nothing to do with radar.
With the high cost of airplane fuel using airplanes are not cost effective so they have not been used for years in Iowa except for newspaper/radio publicity.
On I80 they are in the center lane only and usually 1/4 mile apart but not always. At -93.713974, 41.652737 line if you measure left , the next line is 1/4 mile but if you measure right, the next line is .17 mile away. In Iowa they do not span the road but usually in the center of one lane.
If your state has money to throw away and you get a ticket from the airplane I suggest you check to see how your lines are spaced.

VA does use them. At least the lines are freshly painted. There are a pair of them in the West bound lane @ 37.34523, -76.72274 (Lat., Lon.). They are 1/4 mile apart.

Never seen Troopers working them though, although my son claims that he sees Troopers working them all the time in Richmond.

If the engineer used a tape measure, then lines must have been close together. The closer together, the larger the error created.

Maybe someone that remembers algebra better than me can figure out the distance between the lines in question. I think the article mentioned the speed limit and the speed on the ticket.

I think that the one foot error didn't really make that much difference in the speed recorded. Most likely is more of the fact that the engineer proved that the distance of the lines was incorrect, therefore the speed was incorrect.

Years ago, in VA Beach, there was a Navy Chief Fire Control Technician that beat a radar ticket by similar means. (For those of you who don't know, Fire Control is controlling Naval Gunfire and Missiles. By the very nature of their job use Trig and angles for firing solutions.)

This Chief told the judge that the speed recorded by the radar was incorrect and could prove it. The judge agreed if he proved it wrong he would dismiss it. As most of you know, most police officers sit off the side of the road or in the median. The radar beam is never directly in line with the the actual travel of the vehicle, but strikes the vehicle at somewhat of an angle. The Chief was able to show by right triangles and Trig that the speed measured was actually slower than the vehicle was really moving. While he was speeding, the radar calculated an incorrect speed. The Judge dismissed the charge because the reading was incorrect. Not because he wasn't speeding.

There's an area near me that uses aircraft enforcement for speed limits on the interstate. The lines aren't even painted the whole way across the road, they're only in the breakdown lanes. I don't know how often they do it - they certainly don't have planes in the air every day, but I know a few people that have been ticketed by aircraft there.

The last time I visited Pennsylvania, they still relied on aircraft enforcement. And no, I didn't get pulled over.

Uses aircraft, they park 6 or 7 squad cars on a I90/Rt2 on ramp. Getting their prey from a circling Ohio Highway Patrol aircraft. Using lines painted in the shoulder lane.
They do this several times a year, however radio stations usually give a heads up on the ten's.

I'm not a science guy: I'm a knuckle dragger.

The closest I've come to actual science, was naming my cat 'Schrodinger'.

You're talking about what is called the Cosine Effect.
Cosine always favors the moving object.

The greater the angle the RADAR antenna is from the travelway, the lower the target reading, but the object is always moving faster.

In your example, if the Cop testified he tested the instrument's internal circuitry (don't over think it: it takes a press of a button on the instrument), and checked that the display unit could read the test forks correctly, the target display was actually correct.

If your example is correct, my guess is the Cop didn't understand Cosine or his instrument, and could not explain it properly to the court's satisfaction, and the judge dismissed it because of that.

VASCAR is also being discussed

VASCAR is not a top speed:
It is the average speed the vehicle was traveling between the start and stop points.

None of my spots have a distance less than 528 feet, or one tenth of a mile.

When used properly, VASCAR has no more than a +-.003 mph variance.

Longer distances cause even less +- variance.
None of my VASCAR spots have a distance less than 528 feet, or one tenth of a mile.

I won't use VASCAR where the speed limit is less than 55mph.

I measure my VASCAR points with a Garmin 60GPS color.

I start my chronometer before the object hits the start point, and end after the object passes the stop point.

This always favors the traveling object, and testify to this in court.

It shows the court, that the object's average speed was actually faster than shown on the display.

I use a Robic Chronometer, that I can program in the distance.

It gives me the time the vehicle traveled, as well as the average speed.

At trial, I give the court and defendant a copy of the scientific VASCAR formula, and the formula as it applies in the driver's specific case.

For RADAR, I give them a copy of the latest annual instrument check, performed by the manufacturer's authorized tech.

I've never lost a RADAR or VASCAR case.

I don't use LIDAR, not that it doesn't work, but because of the new power limitations on the actual laser, it makes it IMHO, worthless as a traffic tool.

FWIW, fastest speed I've got on RADAR: 113/65
Fastest on VASCAR: 113/75

Edit to add:
I'm a big fan of countermeasures.

In my POV's, I have Valentine 1's, LIDAR diffusers, as well as LIDAR absorbing license plate covers, and of course, the red light/speed camera poi's in my Garmin's.

There's not much defense from VASCAR.

Jay

Read the article at source. As typical for the media, there are a complete lack of facts making it impossible to assess the situation with anything but pure emotion and opinion.

Good for him! Only an engineer would attempt to do this.

I'm sure there are places that still enforce speed with aircraft on occasional shifts each year but mostly for show and publicity. I'd expect they use patrol cars without aircraft way more often.

Speed enforcement by aircraft is just too expensive to be worthwhile figuring the amount the police have to spend for the the pilot and officer time, fuel, and wear-and-tear on plane/chopper and cars. It's an easy target to cut from squeezed enforcement budgets because the revenue it produces is going to be more out of line with the cost of collecting it than one-squad-car enforcement.

offers free tape measures.

Banned thode Darn *$#$#@ Cameras..
Yea for any win!!!!
reform against cameras...
Vegelante justuce Shoot the damn things.....

This article
http://rawlife.blog.co.uk/2015/01/22/beware-new-motoring-cha...

indicates that the Carmarthenshire Council determined the lines were inaccurately placed.