Airborne Speed Trap Countermeasures - Revisited

Here in FL we have the unfortunate distinction of periodical airborne VASCAR on our highways. This has been a fact of life for as long as I have been driving in this state. By now, it seems that all of the best stretches of highway have white lines across them. Some are old and some are new, but the only time you don't see it is when the road has just been repaved.

It has always bothered me that I can't just go out and get an airplane detector to mount next to my radar detector. Now, thanks to a few postings on this site, I happened to notice that there are a few people who bought Portable Collision Avoidance Systems (PCAS) to use as airplane detectors in their cars. This seems to be such a great Idea, but I haven't seen any reports on actual results on their use.

Has anyone else done this? If so, how did it work out?

I was lucky enough to find a very inexpensive PCAS system on Ebay (for $80 :D) I'm going to try this out, and post what I find here. Unfortunately, aerial speed traps are expensive, so they are not done all the time. This could work out more like spotting Bigfoot than anything else.

The good thing is that in this case, I know that Bigfoot likes the turnpike on busy travel holiday weekends that happen to be sunny.

If anyone has any experience or thoughts on this, please post.

It's a bit of a hike from Sunrise, but I can see the airplane from my house when they're running the trap just south of the Bird Road toll (MM 22ish) on the Turnpike.

That's also pretty close to MIA and Tamiami Airport, so I'm sure you'd have some deciphering to do, but I'd be glad to shoot you a PM if you want me to alert you to the times that they're running it. They often seem to go for 9-11 AM on weekdays.

I know where/when to look for airplanes for that particular trap, but I've been quite curious about implementing some sort of VASCAR countermeasure myself. I haven't done much research on it, but I was under the impression that you couldn't get one of those gadgets for less than $500, so for $80, that's a far cry better than I thought...

I'm curious to hear of your results with it.

Please do shoot me a message when this happens. Sometimes I don't have any work booked (not often though), so I can hop in the car and head on over.

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Originally Posted by switch626

Here in FL we have the unfortunate distinction of periodical airborne VASCAR on our highways. This has been a fact of life for as long as I have been driving in this state. By now, it seems that all of the best stretches of highway have white lines across them. Some are old and some are new, but the only time you don't see it is when the road has just been repaved.

It has always bothered me that I can't just go out and get an airplane detector to mount next to my radar detector. Now, thanks to a few postings on this site, I happened to notice that there are a few people who bought Portable Collision Avoidance Systems (PCAS) to use as airplane detectors in their cars. This seems to be such a great Idea, but I haven't seen any reports on actual results on their use.

Has anyone else done this? If so, how did it work out?

I was lucky enough to find a very inexpensive PCAS system on Ebay (for $80 :D) I'm going to try this out, and post what I find here. Unfortunately, aerial speed traps are expensive, so they are not done all the time. This could work out more like spotting Bigfoot than anything else.

The good thing is that in this case, I know that Bigfoot likes the turnpike on busy travel holiday weekends that happen to be sunny.

If anyone has any experience or thoughts on this, please post.

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Seems very promising .

In Quebec province they are using air surveillance again after 12 years of abandon .

Not sure to understand everything ... do all small planes reported by the system or do the plane needs a special equiment to be reported ?

Zaon Flight Systems - Zaon Now Integrates with Garmin Aera Series

Thanks.

The system actually works by means of the signal transmitted by the transponders on most aircraft. To my knowledge, the transponders could be turned off during Visual Flight Rules flying (which I think is what a speed trap would require). However, it appears that pilots generally do not turn them off even of they can, since they are used by collision avoidance systems.

Presumably, even VFR pilots would like to avoid collisions,and this should take precidence over writing tickets.

This idea has been used before by they guy who invented the Fuzzbuster. The device was called Spybuster, but has pretty much disappeared. I don't know why it is no longer available. There is one account in here of a guy who used the Spybuster with good results.

There are also two people in here that have tinkered with PCAS systems before. They never did post about any road tests though. This looked promising, but their threads have closed.

I suspect this is technique would find limited use, even if it works well. Only a handful of states and some Canadian provinces seem to use airborne VASCAR. Add to that the cost of a new PCAS system (usually around $450), and the typically limited use of this type of trap, and the benefit does not justify the cost for many people. I also figure there would be too many falses for this to be useful near airports.

That said, Florida is definitely a place where using PCAS could make sense. Most of the best highways have ample lines on them. This is often to the point that you have to either choose to slow down or ignore the lines and assume that there is no plane overhead watching (which is usually correct).

Anyway, this is a good place to test because this method is used extensively here. If it works out, then there is a decent tool against airborne VASCAR for those who don't mind spending the money on it.

even VFR pilots generally do not turn off their transponder (aka squawk box) You may be onto something here. Generally FHP is flying around 2500 ft. Getting a warning when you are under them is not much notice. What is the range of the TCAS system.

Thanks Switch626 , here they will use vascar for 212 hours
as a test and see if it is profitable $ecuritarily :rolleyes:

My wife had , 15 years ago a vascar ticket ...I was passenger with my
Solo detector ...they had pulled over like 5 cars at this time ....the guy
in the sport mercedes was mad like hell ... we were his rabbit

Would it be a good idea : paint the top of a car a different color ....
a desesperate way to fight vascar ?

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Originally Posted by Eloi

Thanks Switch626 , here they will use vascar for 212 hours
as a test and see if it is profitable $ecuritarily :rolleyes:

My wife had , 15 years ago a vascar ticket ...I was passenger with my
Solo detector ...they had pulled over like 5 cars at this time ....the guy
in the sport mercedes was mad like hell ... we were his rabbit

Would it be a good idea : paint the top of a car a different color ....
a desesperate way to fight vascar ?

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LMFAO that would be hilarioius but you'd have to paint the trunk and hood a different color to

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Originally Posted by Riptide

Quote:

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Originally Posted by Eloi

Thanks Switch626 , here they will use vascar for 212 hours
as a test and see if it is profitable $ecuritarily :rolleyes:

My wife had , 15 years ago a vascar ticket ...I was passenger with my
Solo detector ...they had pulled over like 5 cars at this time ....the guy
in the sport mercedes was mad like hell ... we were his rabbit

Would it be a good idea : paint the top of a car a different color ....
a desesperate way to fight vascar ?

---

LMFAO that would be hilarioius but you'd have to paint the trunk and hood a different color to

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Hilarious yes , but as technology advances they are coming with
switchable paint , under voltage the paint will change tone ....but we could
be all old when it becomes available :D

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Originally Posted by thx1138

even VFR pilots generally do not turn off their transponder (aka squawk box) You may be onto something here. Generally FHP is flying around 2500 ft. Getting a warning when you are under them is not much notice. What is the range of the TCAS system.

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The unit I ordered is pretty old, and is out of productions. This is making it a little difficult to find a proper manual, but I have been able to find some information posted about. From what I have seen posted, it is able to detect an airplane from 5 to 10 nautical miles out, depending on the mode it is in.

It's also important to note that this is a TPAS, so it does not interrogate the aircrafts transponder. Instead, it listens for the transponder to respond to other interrogating signals from a TCAS or Air Traffic Control. This passive aspect of the device means that if you are in an area that has no radar or airplanes around, you probably will not detect anything.

It is also worth mentioning that the distance estimation of the device is accurate to withing 1800'. Although some similar systems will give you an actual altitude (depending on the capabilities of the transponder in question), mine will not. This all seems very much like the Spybuster.

I wonder if anyone makes one of these that DOES INTERROGATE. That would make this much more attractive.

Quote:

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Originally Posted by Eloi

Thanks Switch626 , here they will use vascar for 212 hours
as a test and see if it is profitable $ecuritarily :rolleyes:

My wife had , 15 years ago a vascar ticket ...I was passenger with my
Solo detector ...they had pulled over like 5 cars at this time ....the guy
in the sport mercedes was mad like hell ... we were his rabbit

Would it be a good idea : paint the top of a car a different color ....
a desesperate way to fight vascar ?

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Maybe paint it a similar color to FHP :D

I like the idea, although I would also think you are looking for a color that is not reflective of lidar. Or maybe a diagonal stripe pattern to create an optical illusion, this making it harder to accurately track.

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Originally Posted by switch626

Or maybe a diagonal stripe pattern to create an optical illusion, this making it harder to accurately track.

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The ole Zebra stripes confusing the Lion theory here. We being the Zebra and the LEO's being the Lion. ;)

I like what your trying to do/experiment with here though:thumb2:.
Let us all know how it turns out, because if you can make it work could definitely make life easier for all of us who haft to worry about this type of enforcement tactic. :cool:

Good luck!

switch, I have a pilot friend over in your area. If you are interested I could arrange a test against a regular single engine fixed gear aircraft. Pick a stretch of road and fly a simulated enforcement run. PM me if you want to try this idea

this is something I have thought about getting. but wanted concrete evidence that it will work.

I hope you guys get something setup to run a controled test to see if it will work.

Quote:

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Originally Posted by Eloi

Thanks Switch626 , here they will use vascar for 212 hours
as a test and see if it is profitable $ecuritarily :rolleyes:

My wife had , 15 years ago a vascar ticket ...I was passenger with my
Solo detector ...they had pulled over like 5 cars at this time ....the guy
in the sport mercedes was mad like hell ... we were his rabbit

Would it be a good idea : paint the top of a car a different color ....
a desesperate way to fight vascar ?

---

Silver vehicles are more difficult to pick out from the air as they tend to blend in with the pavement. So use silver for the top of your car.:D

For Florida, I would think a CB radio would be a great countermeasure for air enforcement.

GTO_04

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Originally Posted by lugnuts

this is something I have thought about getting. but wanted concrete evidence that it will work.

I hope you guys get something setup to run a controlled test to see if it will work.

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I haven't quite figured out how to do a controlled experiment yet, so I am hoping to hear from anyone who has and idea of how to approach that.

I'm definitely planning to do some road testing when I get it.

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Originally Posted by GTO_04

Quote:

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Originally Posted by Eloi

Thanks Switch626 , here they will use vascar for 212 hours
as a test and see if it is profitable $ecuritarily :rolleyes:

My wife had , 15 years ago a vascar ticket ...I was passenger with my
Solo detector ...they had pulled over like 5 cars at this time ....the guy
in the sport mercedes was mad like hell ... we were his rabbit

Would it be a good idea : paint the top of a car a different color ....
a desesperate way to fight vascar ?

---

Silver vehicles are more difficult to pick out from the air as they tend to blend in with the pavement. So use silver for the top of your car.:D

For Florida, I would think a CB radio would be a great countermeasure for air enforcement.

GTO_04

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I have also heard that silver is very hard for lidar reflections. That makes a nice double whammy. I am leaning toward my next car being silver.

I think the CB is definitely a tried and true countermeasure for this. I think the collision avoidance method would be a good addition though if it works. These methods seem to both have their weaknesses, but together would fill in the gaps.

Silver might make you an easier lidar target.

Seriously if you want to try the TCAS in a controlled experiment, I can get an airplane to fly patterns and you approach the simulated enforcement area and see how the TCAS reacts. This would be way easier that trying to chase down an actual airplane trap.

Experiment is as follows...
Pick a road, specific location on that road and a time. Airplane flys at 2500ft in a racetrack pattern, 1 mile legs. Target car, drives through the simulated enforcement area observe the TCAS. Target car drives beyond the target area by 2 miles and does a U-turn. Repeat the drive through and repeat observations. Do this 3-5 times.

Optionally you could video both the airplane and car cabins, note the exact GPS coordinates of both the car and the aircraft. Ground to air communication would be good, and you would need an aircraft two way radio (I have one BTW).

I'd suggest a road way out west Broward or Palm beach county, such as US27, SR80 or the Sawgrass--- somewhere way out of controlled airspace and on a road that has long straightaways and the ability to make U turns.

Just let me know if you really want to test this out.

Quote:

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Originally Posted by thx1138

Silver might make you an easier lidar target.

Seriously if you want to try the TCAS in a controlled experiment, I can get an airplane to fly patterns and you approach the simulated enforcement area and see how the TCAS reacts. This would be way easier that trying to chase down an actual airplane trap.

Experiment is as follows...
Pick a road, specific location on that road and a time. Airplane flys at 2500ft in a racetrack pattern, 1 mile legs. Target car, drives through the simulated enforcement area observe the TCAS. Target car drives beyond the target area by 2 miles and does a U-turn. Repeat the drive through and repeat observations. Do this 3-5 times.

Optionally you could video both the airplane and car cabins, note the exact GPS coordinates of both the car and the aircraft. Ground to air communication would be good, and you would need an aircraft two way radio (I have one BTW).

I'd suggest a road way out west Broward or Palm beach county, such as US27, SR80 or the Sawgrass--- somewhere way out of controlled airspace and on a road that has long straightaways and the ability to make U turns.

Just let me know if you really want to test this out.

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I suggest you take this man up on his generous offer. This would be the first time ever this type of thing has been tested and documented.

The fastest quick test would be to pick a small airport and see how your TCAS works. Determine which runway is active. Park your car under the downwind or final leg of the landing aircraft. Your TCAS should be alerting as aircraft fly over you. You have several airports to choose from (Exec-commercial Blvd, Pompano, Boca, Lantana). Traffic will only be 1000-1500 ft on downwind and lower on final, so this isn't a realistic test.

I'd suggest you try that first to confirm everything is working before a more realistic test and extensive test is performed.

Quote:

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Originally Posted by thx1138

Silver might make you an easier lidar target.

Seriously if you want to try the TCAS in a controlled experiment, I can get an airplane to fly patterns and you approach the simulated enforcement area and see how the TCAS reacts. This would be way easier that trying to chase down an actual airplane trap.

Experiment is as follows...
Pick a road, specific location on that road and a time. Airplane flys at 2500ft in a racetrack pattern, 1 mile legs. Target car, drives through the simulated enforcement area observe the TCAS. Target car drives beyond the target area by 2 miles and does a U-turn. Repeat the drive through and repeat observations. Do this 3-5 times.

Optionally you could video both the airplane and car cabins, note the exact GPS coordinates of both the car and the aircraft. Ground to air communication would be good, and you would need an aircraft two way radio (I have one BTW).

I'd suggest a road way out west Broward or Palm beach county, such as US27, SR80 or the Sawgrass--- somewhere way out of controlled airspace and on a road that has long straightaways and the ability to make U turns.

Just let me know if you really want to test this out.

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I definitely want to do this. I expect the TPAS to be delivered on the 13th. I will probably want to play with it and get familiar before we spend any time on a proper test like this. I'm looking forward to doing this.

Quote:

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Originally Posted by thx1138

The fastest quick test would be to pick a small airport and see how your TCAS works. Determine which runway is active. Park your car under the downwind or final leg of the landing aircraft. Your TCAS should be alerting as aircraft fly over you. You have several airports to choose from (Exec-commercial Blvd, Pompano, Boca, Lantana). Traffic will only be 1000-1500 ft on downwind and lower on final, so this isn't a realistic test.

I'd suggest you try that first to confirm everything is working before a more realistic test and extensive test is performed.

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I will definitely spend some time with the TPAS before any serious testing. I could probably do it right here at home. It seems the landing pattern for FLL is near my house.

Quote:

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Originally Posted by switch626

I think the CB is definitely a tried and true countermeasure for this. I think the collision avoidance method would be a good addition though if it works. These methods seem to both have their weaknesses, but together would fill in the gaps.

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True, the more countermeasures you have the better, especially with air enforcement.

Quote:

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Originally Posted by switch626

I have also heard that silver is very hard for lidar reflections. That makes a nice double whammy. I am leaning toward my next car being silver.

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I have not heard that before. I sure hope it is true though!

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Originally Posted by thx1138

Silver might make you an easier lidar target.

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That is probably more likely. But don't they normally they target your plate or headlights? Ideally for laser protection (along with a jammer),you would want black, non-metallic paint, popup headlights, and no front plate. Or maybe two-tone paint, black with a silver hood and roof.:D

GTO_04

Quote:

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Originally Posted by switch626

I will definitely spend some time with the TPAS before any serious testing. I could probably do it right here at home. It seems the landing pattern for FLL is near my house.

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I'll have a plane and pilot available when you are ready. I wonder if one more forum member could meet us. One driver (switch), one passenger to record the TCAS alert locations and one for the plane to assist the pilot and record info.

Quote:

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Originally Posted by thx1138

Quote:

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Originally Posted by switch626

I will definitely spend some time with the TPAS before any serious testing. I could probably do it right here at home. It seems the landing pattern for FLL is near my house.

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I'll have a plane and pilot available when you are ready. I wonder if one more forum member could meet us. One driver (switch), one passenger to record the TCAS alert locations and one for the plane to assist the pilot and record info.

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I'd love to join you guys, but I'm a little far away to do it. :(

Get a scanner(s) programmed for highway patrol and one for the police aviation unit.

FHP has gone encrypted digital since 2005. :(

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I wonder if anyone makes one of these that DOES INTERROGATE. That would make this much more attractive.

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Yes, they exist, but they are usually hardwired to the electrical system. And they cost a lot more than what you paid for this one. :)

Quote:

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Originally Posted by thx1138

FHP has gone encrypted digital since 2005. :(

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Damn :(

The TPAS came in Yesterday, so of course I took it down to a side street that is perfectly aligned with West side of the runway (where planes are usually coming in for a landing). This gave me a good opportunity to . Play with the controls and get an idea of how it works.

Unfortunately, this model is so old and obsolete, that I was not able to find a manual for it. I did find a couple of really old articles written about the TPAS when it was a brand new model. They gave a pretty good description of how to use it for it's intended purpose. The Ebay seller assured me that this device would be easy to figure out, and so far it has been.

I basically just plugged in a set of headphones (since my car doesn't have the intercom system that a plane would have, and sat and watched as planes came in.

There are two sensitivity settings: TCA, and ENROUTE. TCA seems to be more accurate in estimating the distance of an approaching plane, and also only sounds an alert when the plane is nearly right on top of you. It also doesn't seem to track anything over 4 nautical miles.

Enroute, on the other hand, is far less precise. It also tracks planes at much greater distances. I think I saw it mentioned somewhere that this mode tracks up to 15 miles. It also seems to alarm around 2 miles out.

After a while sitting near the runway, I decided to follow SR84/I595 further out. I was hoping to encounter traffic at higher altitudes, and get an idea if there was any kind of a ceiling on either mode. Unfortunately, the alerts we so abundant that It like there practically was a plane any more than 3 miles out. Since I was driving, I didn't always get to spot the plane in question, but often I did. Still, with the alarms so frequent, I was starting to worry that I was getting a whole lot of false alerts.

At one point, I stopped at a convenience store, so my girlfriend could get a pack of cigarettes. While she ran in, I turned the motor off, and sat watching with the windows down and sun roof open. Sure enough, I got an alert in TCA mode for a plane 1 mile out. About a mile to the north of me, a plane! He still wasn't very high though.

I continued westward onto Alligator Alley, and finally parked at the second recreational area. By this time the alerts were finally stopping much of the time. The traffic I was getting was now often 3 or more NM out. Then finally, an alert! There was a plane within a mile of my location. I got out of the car and started to scan the sky for my bogey, and there it was. I would guess that this plane was at about 5 thousand feet and no more than a mile away. I'm pretty sure that I will have no problem with planes watching cars from 2500 feet.

Let me sync up on schedules, plane/pilot availability and a suitable location. Do you have the capability to video the device in action during the flyover encounter?

Quote:

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Originally Posted by thx1138

Silver might make you an easier lidar target.

Seriously if you want to try the TCAS in a controlled experiment, I can get an airplane to fly patterns and you approach the simulated enforcement area and see how the TCAS reacts. This would be way easier that trying to chase down an actual airplane trap.

Experiment is as follows...
Pick a road, specific location on that road and a time. Airplane flys at 2500ft in a racetrack pattern, 1 mile legs. Target car, drives through the simulated enforcement area observe the TCAS. Target car drives beyond the target area by 2 miles and does a U-turn. Repeat the drive through and repeat observations. Do this 3-5 times.

Optionally you could video both the airplane and car cabins, note the exact GPS coordinates of both the car and the aircraft. Ground to air communication would be good, and you would need an aircraft two way radio (I have one BTW).

I'd suggest a road way out west Broward or Palm beach county, such as US27, SR80 or the Sawgrass--- somewhere way out of controlled airspace and on a road that has long straightaways and the ability to make U turns.

Just let me know if you really want to test this out.

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I would like to go ahead with this when it is convenient. I'm thinking that US27 would probably be a good place for it. It is somewhat remote, and provides the ability to make u-turns.

Filming would be good, though I could use a volunteer to do filming (especially if they have a good cam). We will definitely also need the two way radio.

Do you know which airport your pilot friend would be flying out of? Maybe we could choose an area not too far from there in order to not use a pile of avgas.

On Wednesday I finally got a chance to put the TPAS on my dash and take a little road trip. The weather wasn't really suitable for an actual encounter with an airborne speed trap, but I figured there would still be planes in the air.

Mounting the device on my dash proved to be a little more challenging than I expected. This was mainly because of the antenna in the back needing to be vertical in order to work. This was not a good combination with the slope of the windshield and the limited dash space in the Celica. I eventually just stuck it on the dash with two sided tape. Crude but effective.

Since headphones are not really practical (and are illegal when driving), I threw a set of cheap computer speakers on the floor and plugged them into a cheap power inverter. It looked like hell, but the traffic alerts that come in the form of a pleasant female voice sounded much better.

Ideally, I am going to get an extension cable for the antenna and a shorter stereo so there will be room for the TPAS to be mounted in the opening that is meant for the stereo. I'm thinking the new stereo should have an aux port, so I can plug the sound from the TPAS into it.

Today's trip was from Fort Lauderdale to Clewiston and back on US27. There was active ATC radar on most of the trip, but thankfully there were also areas that had none. It appears that while we were in range of ATC radar, the TPAS was very reliable pointing our air traffic at various ranges.

In the areas where we were not in range of Air Traffic Control radar, we were still detecting planes. Under these conditions the detections were more sporadic, as the only source of interrogation was from other planes. Still, I was often detecting planes 7 or 8 miles away.

I often found myself toggling between TCA mode (close range) and Enroute Mode (long range), depending on how far the nearest plane was. I fond that I am getting a preference for Enroute mode, because it starts the audible warnings around 1.5 to 2 nautical miles out.

Overall, I am growing more confident that this device will prove to be an effective countermeasure for airborne speed traps. So much so, that I am planning a permanent install in my car.

Since the TPAS that I am testing in no longer in production or widely available, I would like to post a link to a device that IS currently available for around 500 dollars.

Zaon Portable Collision Avoidance System - PCAS MRXA-A - MyPilotStore.com

This is mentioned in other threads in here, but I never found any actual test results, or even road testing commentary. Here are the links that I found:

http://www.radardetector.net/forums/...highlight=pcas

http://www.radardetector.net/forums/...highlight=pcas

^^^

Ok, Ok... what I want to know: Who has the PINK Crocs on!?! :p

The plane is based in Lantana (LNA) just south of West Palm. I'll get hold of the pilot this weekend. Alligator alley or US27 should work just fine. Another forum member maybe able to join us. Thinking about next Saturday (7/24) to attempt this. If that date is good for you I'll try to line up the pilot/plane and the 3rd forum member (Dr Coke). I have an extra aircraft two way radio and a small video camera to record the events in the car.

I am a pilot - at first I thought this would not work - but it might. The only other issue is you will still get a lot of falses from other aircraft, especially if you are near an airport.

Found this owner's manual.

http://www.zaon.aero/component/optio...ownload/gid,1/

i'm sure this is when a police scanner earns its keep. Also the cb, truckers will tipoff that some kind of speedtrap is in play ahead.

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Originally Posted by superbolt

i'm sure this is when a police scanner earns its keep. Also the cb, truckers will tipoff that some kind of speedtrap is in play ahead.

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Absolutely true. Better to just pick up a handheld scanner and find out what frequencies are used between aircraft and ground units. Most air-to-ground for traffic enforcement is done using regular aviation frequencies.

Also, eyes help...

http://www.radardetector.net/forums/...rce-again.html

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Originally Posted by OpenRoad

I am a pilot - at first I thought this would not work - but it might. The only other issue is you will still get a lot of falses from other aircraft, especially if you are near an airport.

Found this owner's manual.

http://www.zaon.aero/component/optio...ownload/gid,1/

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I like the PCAS you link to alot. It has a major advantage over the TPAS that I am using in that you can define a proximity to your altitude for up to 5000'. This would help to weed out airliners at cruising altitude that are not a threat.

My TPAS makes no distinction based on altitude.

Still, neither unit can distinguish a speed enforcement aircraft from any other aircraft. Whit this means to me is that one needs to consider both the proximity of the aircraft in question AND the presence of VASCAR lines on the road surface. IE:

Plane close by and no lines = go fast
No plane close by but lines present = go fast
Plane close by AND lines present = GO SLOW NOW