CB Antennna Tripping Bridge Height Sensor

UK PROFESSIONAL DRIVERS FORUMS THE UK PROFESSIONAL DRIVERS FORUM (INTERACTIVE)
1

Is it an offence to drive on through?

I know the height of the bridge in question and the exact height of my trailer(s) as I have measured them and know that there is more than enough clearance to pass under safely.

Would like to know what the legal standpoint is on this. Am I breaking the law ignoring a warning sign? Even though I know it is in error?

The bridge in question is at Dunragit, on the A75 just outside Stranraer. It’s height is 14’ 3" (4.35m) and my trailer is 13’ 5" (4.10m).

Breaker One-Nine
10-4! Let Them Truckers Roll!

2

It probably is an offence if the warning says “STOP”.

Also many bridges have telephone cables and other clutter underneath that could be damaged, or cause damage/electric shock to you throught the CB aerial.

3

Unless it’s been changed I’m sure that sign says…

“over height vehicle divert ----->”

So if your vehicle isn’t ‘over height’ then you should be okay to proceed without commiting an offence.

But… does the CB aerial count as vehicle height? I think it might.

4

I wouldnt have thought a cb aerial would be thick enough to trigger the sensor as it would be too thin to block the beam.

Unless of course you are running SATELLITE communications, :laughing:

5

slightly different but when we used to go through blackwall tunnel with a tilt trailer, if you were under 20 mph no problem anything over used to cause the sheet to inflate on top, this then triggered alarms.

Trailer would go through the tunnel but if you set off the alarms you had to divert.

6

It’s only a short diversion if you set the the lights off,remember the lights being out of order ,big signs up warning drivers,one lorry up from the boat hit hit the bridge and finished up parked in the middle of that wee field,took a bit of getting out,I think the driver hit the windscreen when the truck hit the bridge,not nice.
regards derek

7

toowise:
slightly different but when we used to go through blackwall tunnel with a tilt trailer, if you were under 20 mph no problem anything over used to cause the sheet to inflate on top, this then triggered alarms.

Trailer would go through the tunnel but if you set off the alarms you had to divert.

I’ll second that.

8

Used to go along the A75 a lot my trailer was a decker so used the diverson, it does just flash up “overheight vehicle divert”

Strange the CB aerial activating the sensor, run down there solo a few times and gone up the bridge never had the sign light up but have heard the ting of the cb aerial hitting the bridge.

9

done the blackwall with a euroliner once and never again i’ll take my chances at the ferry or dartford from now on

10

Youve plenty room bud if its a 13ft 5"… Start worrying when your runnign a Roadferry 15ft 5"… Mcb’s, Montys etc all get under… You must be runnign a thick aerial??

11

It must be the aerial. Couldn’t be anything else. The strange thing is it only trips the sensor going towards the Boat. Coming off and heading south is always okay…?

Answers on a postcard. In the meantime im under the bridge as always :smiley:

12

Breaker One-Nine:
It must be the aerial. Couldn’t be anything else. The strange thing is it only trips the sensor going towards the Boat. Coming off and heading south is always okay…?

Answers on a postcard. In the meantime im under the bridge as always :smiley:

Only time i ran solo i was heading from the boat, always had a trailer on coming back. So maybe it would have tripped the sensor if i was running solo because of the aerial.

13

Just unscrew the aerial at the base before you go under it. :wink:

14

Breaker One-Nine:
The strange thing is it only trips the sensor going towards the Boat. Coming off and heading south is always okay…?

It could be that the aerial is closer to the sensor when going towards the boat, this might make it easier to detect.