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Matt5860
Hi, I was driving at night at 35 mph in a 30 zone, a police van was coming down the road on the opposite side. I was wondering if all police cars/vans have the equipment to monitor speed or just the motorway patrol cars? This happened around a town. Are they able to monitor you from the opposite side or only when they are following you?

In this situation where a car picks you up as speeding, would they normally pull you over there and then rather than send a ticket?

Cheers
AntonyMMM
All they need is a pair of eyes and a method of confirming their opinion (a speedometer will do) , but you are worrying about nothing. At 35 in a 30 they will not even have noticed you, and if that is what your speedo said, your true speed would probably be closer to 32/33.
The Rookie
No UK system can measure your speed from a moving vehicle while travelling the opposite direction (well time and distance devices can in theory, but in practice it's next to impossible).
13152
QUOTE (The Rookie @ Mon, 2 May 2016 - 16:38) *
No UK system can measure your speed from a moving vehicle while travelling the opposite direction (well time and distance devices can in theory, but in practice it's next to impossible).

That isn't right. VASCAR operators are trained to measure the speed of approaching vehicles and it is very easy to do.

Have you any experience of operating VASCAR devices?
peterguk
QUOTE (13152 @ Wed, 4 May 2016 - 12:10) *
VASCAR operators are trained to measure the speed of approaching vehicles and it is very easy to do.


VASCAR doesn't measure the speed of anything. It simply measures the time take for the target vehicle to travel a known distance, so i guess in theory it could be used to for oncoming vehicles, but whether it's easy in practice, i have no idea.
Jlc
In the context of the original question it would be extremely unlikely that the Police van would have VASCAR'd the OP to the recommended minimum distance and even if they did 33mph or so wouldn't exactly make them want to handbrake turn to catch the rotten criminal.
13152
QUOTE (peterguk @ Wed, 4 May 2016 - 14:17) *
QUOTE (13152 @ Wed, 4 May 2016 - 12:10) *
VASCAR operators are trained to measure the speed of approaching vehicles and it is very easy to do.


VASCAR doesn't measure the speed of anything. It simply measures the time take for the target vehicle to travel a known distance, so i guess in theory it could be used to for oncoming vehicles, but whether it's easy in practice, i have no idea.

If a device measures "the time taken(sic) for the target vehicle to travel a known distance" then the device has measured the speed of the target vehicle because the speed of the taget vehicle is the time taken(sic) for the target vehicle to travel a known distance.

You might want to look for some more hairs to split perhaps. smile.gif

QUOTE (Jlc @ Wed, 4 May 2016 - 14:35) *
In the context of the original question it would be extremely unlikely that the Police van would have VASCAR'd the OP to the recommended minimum distance and even if they did 33mph or so wouldn't exactly make them want to handbrake turn to catch the rotten criminal.

Agreed that it is unlikely to have triggered a speed measurement in the situation described.

I can't see how you would assess whether the minimum distance would have been used, it is only 0.07mile for speed limits of 40mph or below.
Jlc
0.07mile would be under exceptional circumstances - clearly unlikely here. In a pre-set situation maybe.
13152
QUOTE (Jlc @ Wed, 4 May 2016 - 17:26) *
0.07mile would be under exceptional circumstances - clearly unlikely here. In a pre-set situation maybe.

Say's who?
The Rookie
QUOTE (13152 @ Wed, 4 May 2016 - 12:10) *
QUOTE (The Rookie @ Mon, 2 May 2016 - 16:38) *
No UK system can measure your speed from a moving vehicle while travelling the opposite direction (well time and distance devices can in theory, but in practice it's next to impossible).

That isn't right. VASCAR operators are trained to measure the speed of approaching vehicles and it is very easy to do.

Have you any experience of operating VASCAR devices?

Not operating, but I know a few traffic cops on a personal level.

Approaching while you are stationary yes, approaching while you are moving as in this case?

0.07 of a mile takes 2.1 seconds at 30mph, the margin for error is then huge, just an 1/8 of second on the timing at each end is then a 12% error without any distance error. I think someone trod in something.....
Jlc
QUOTE
THE MINIMUM DISTANCE FOR ANY CHECK IS GENERALLY 1/8 OR .125 OF A MILE.

However checks over a shorter distance, down to an absolute minimum of 0.07 of a mile are permissible under the following circumstances:-

a) The general minimum can only be reduced for Pre-fed or Dial-in Distance Checks.
b) The reference points at both the start and end of the check are physical features on the road surface which provide a clear and visual contact. (e.g.. white line/change of surface) NOT shadows.
c) The maximum speed limit at the site does not exceed 40mph.
13152
QUOTE (Jlc @ Thu, 5 May 2016 - 09:53) *
QUOTE
THE MINIMUM DISTANCE FOR ANY CHECK IS GENERALLY 1/8 OR .125 OF A MILE.

However checks over a shorter distance, down to an absolute minimum of 0.07 of a mile are permissible under the following circumstances:-

a) The general minimum can only be reduced for Pre-fed or Dial-in Distance Checks.
b) The reference points at both the start and end of the check are physical features on the road surface which provide a clear and visual contact. (e.g.. white line/change of surface) NOT shadows.
c) The maximum speed limit at the site does not exceed 40mph.


So not in exceptional circumstances then!

QUOTE (The Rookie @ Thu, 5 May 2016 - 09:44) *
QUOTE (13152 @ Wed, 4 May 2016 - 12:10) *
QUOTE (The Rookie @ Mon, 2 May 2016 - 16:38) *
No UK system can measure your speed from a moving vehicle while travelling the opposite direction (well time and distance devices can in theory, but in practice it's next to impossible).

That isn't right. VASCAR operators are trained to measure the speed of approaching vehicles and it is very easy to do.

Have you any experience of operating VASCAR devices?

Not operating, but I know a few traffic cops on a personal level.

Approaching while you are stationary yes, approaching while you are moving as in this case?

0.07 of a mile takes 2.1 seconds at 30mph, the margin for error is then huge, just an 1/8 of second on the timing at each end is then a 12% error without any distance error. I think someone trod in something.....

Approaching while you are moving is a normal operating mode. I've trained operators to do it and it may surprise you it is one of the most accurate ways of operating.

Hopefully you are now more aware. smile.gif Mind where you put your feet in future.
Jlc
QUOTE (13152 @ Thu, 5 May 2016 - 11:14) *
So not in exceptional circumstances then!

Strictly 0.07 is an exception to the 0.125 minimum. wink.gif
13152
QUOTE (Jlc @ Thu, 5 May 2016 - 11:18) *
QUOTE (13152 @ Thu, 5 May 2016 - 11:14) *
So not in exceptional circumstances then!

Strictly 0.07 is an exception to the 0.125 minimum. wink.gif

Strictly so is 1mile.

You should really only comment on what you know about perhaps.
southpaw82
QUOTE (13152 @ Fri, 6 May 2016 - 16:52) *
QUOTE (Jlc @ Thu, 5 May 2016 - 11:18) *
QUOTE (13152 @ Thu, 5 May 2016 - 11:14) *
So not in exceptional circumstances then!

Strictly 0.07 is an exception to the 0.125 minimum. wink.gif

Strictly so is 1mile.

You should really only comment on what you know about perhaps.

And maybe you should obey the rules about having more than one account. TTFN.
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