sallylillian
LIFE MEMBER
After some useful debates, sometimes with some difficult A Frame company executives with severely biased opinion I started a debate with VOSA technical and I thought I would share the final email from them as it sums up neatly the somewhat tenuous position. And this is not about where you can but if you are in the UK.
Responding to your follow-up mail on the above subject to DVSA.
I am providing to you the Department for Transport official line, to give you the official documents and to avoid giving any definite statements that something is or isn't legal. This is because in the end the only legally binding ruling is that of a court of law, rather than that of a government official. However I will try to be some more help, albeit with the same caveat.
The distinction DfT are drawing about type approval is that this only applies to new unregistered motor vehicle and trailers. Towing frame brackets are invariably installed following car type approval and registration. The towing frame itself can't be type approved in isolation. When type approved the towed car isn't capable of being a trailer. At the point when the brackets and frames are installed "in service" legislation is applied instead. The towed car then becomes a trailer when towed, and the Construction and Use requirements for a trailer apply then instead of the type-approval legislation.
The Construction and Use Regulations reg 18 (1) requires "each and every part of every braking system and the means of operation thereof fitted to a vehicle shall be maintained in good and efficient working order and be properly adjusted." An interpretation of this raised in the DfT fact sheet is that if the towed vehicle has servo brakes then that servo might need to be operational for the trailer (towed vehicle) brakes to be sufficiently effective to be in "efficient" order. However it is also possible for the overrun brake with shortening cable from the tow coupling to provide too much brake control force input unless the servo is depleted. Some cheaper systems do not provide a vacuum source to reinstate the servo vacuum so have to be designed like this to get any appreciable brake effort from second and subsequent brake applications. Without depleting the servo the trailer brakes then lock up horribly on first application. This then begs the philosophical question about whether a vacuum servo with no vacuum source is a means of operation of a braking system in good and efficient order, even though the residual brakes for the trailer do help provide the necessary braking effort for a vehicle combination. (Trailer braking efficiency is not defined separately in Regulation 18.) That has never been ruled on in court, hence my first paragraph. However a school of thought to avoid any possible argument is to get the servo operational. as well as the ABS if that is also fitted to the towed car.
You are right it would be good if there actually were some rules or law to specifically address this. However in order to do so would require some amendment to the European braking legislation as UK cannot act in isolation to "gold plate" the existing laws or impose extra-judicial rules. There is no great incentive to do this as we are not aware of incidents of danger arising from towing motor vehicles as trailers . The government view is that strong evidence is required before committing to change, because of the cost of change and a resistance to extra regulation particularly where the political climate is to reduce regulation, and which is why we are where we are.
So I hope this helps those investigating, and thanks to Larry for some useful pointers.
Michael
Responding to your follow-up mail on the above subject to DVSA.
I am providing to you the Department for Transport official line, to give you the official documents and to avoid giving any definite statements that something is or isn't legal. This is because in the end the only legally binding ruling is that of a court of law, rather than that of a government official. However I will try to be some more help, albeit with the same caveat.
The distinction DfT are drawing about type approval is that this only applies to new unregistered motor vehicle and trailers. Towing frame brackets are invariably installed following car type approval and registration. The towing frame itself can't be type approved in isolation. When type approved the towed car isn't capable of being a trailer. At the point when the brackets and frames are installed "in service" legislation is applied instead. The towed car then becomes a trailer when towed, and the Construction and Use requirements for a trailer apply then instead of the type-approval legislation.
The Construction and Use Regulations reg 18 (1) requires "each and every part of every braking system and the means of operation thereof fitted to a vehicle shall be maintained in good and efficient working order and be properly adjusted." An interpretation of this raised in the DfT fact sheet is that if the towed vehicle has servo brakes then that servo might need to be operational for the trailer (towed vehicle) brakes to be sufficiently effective to be in "efficient" order. However it is also possible for the overrun brake with shortening cable from the tow coupling to provide too much brake control force input unless the servo is depleted. Some cheaper systems do not provide a vacuum source to reinstate the servo vacuum so have to be designed like this to get any appreciable brake effort from second and subsequent brake applications. Without depleting the servo the trailer brakes then lock up horribly on first application. This then begs the philosophical question about whether a vacuum servo with no vacuum source is a means of operation of a braking system in good and efficient order, even though the residual brakes for the trailer do help provide the necessary braking effort for a vehicle combination. (Trailer braking efficiency is not defined separately in Regulation 18.) That has never been ruled on in court, hence my first paragraph. However a school of thought to avoid any possible argument is to get the servo operational. as well as the ABS if that is also fitted to the towed car.
You are right it would be good if there actually were some rules or law to specifically address this. However in order to do so would require some amendment to the European braking legislation as UK cannot act in isolation to "gold plate" the existing laws or impose extra-judicial rules. There is no great incentive to do this as we are not aware of incidents of danger arising from towing motor vehicles as trailers . The government view is that strong evidence is required before committing to change, because of the cost of change and a resistance to extra regulation particularly where the political climate is to reduce regulation, and which is why we are where we are.
So I hope this helps those investigating, and thanks to Larry for some useful pointers.
Michael
