Towing a car using an A-Frame

The law when towing a traditional trailer is reasonably clear whether in the UK or Europe. But tow a car behind a motorhome on an A-frame and the situation is not so clear.

There has been some debate around Directive 71/320/EEC and UNECE Regulation 13 concerning braking system type-approval, however this only relates to new vehicles. Motor vehicles and trailers are within the scope of these technical regulations but A-frame devices are not.

The Department for transport (DfT) states – There is no harmonised EU legislation concerning the type-approval of A-frames and they cannot be considered as vehicles in the context of the legislation as they merely form a link between two vehicles. However, for many years the DfT was clear that the use of devices such as A-frames, spectacle lifts and dollies were intended only for the purposes of recovery of broken down vehicles.

The current DfT information sheet on this subject states: We believe the A-frame and car become a single unit and as such are classified in legislation as a trailer.

It is our understanding that the use of A-frames to tow cars behind other vehicles is legal (in the UK) provided the braking and lighting requirements are met. However on the Continent most countries still see it as a recovery tool and the DfT believes the Vienna Convention 1968 on Road Traffic cannot be used as a defence in disputes because the A-frame would not have been forseen at the time of the Convention.

Therefore the Club strongly advises you abide by the local laws for each country you travel through. In practice this means putting the car on a trailer.

A number of Club members towing with A-frames on the continent have been stopped by local police. In several cases in Spain, police officers have insisted on the decoupling of the A-frame and separate travelling, so be prepared for your partner or travelling companion to drive the car if requested.

Lighting is one issue that can be largely resolved by a connection to the motorhome electrics so all the car’s normal road lights function correctly. The regulations require a trailer to display two red triangular reflectors – which are often overlooked – and also to display the number plate of the towing vehicle.

Braking requirements are not so easy to comply with as many A-frame systems use a relatively simple overrun (also known as an inertia) braking system, as used on caravans, to operate the car’s brakes. The DfT comments on its sheet: If the trailer braking system has power assistance it is likely that this assistance will be required while in motion to meet the required braking efficiencies.

There are also concerns about the ability to reverse a car on an A-frame when using an inertia braking system. Traditional braked trailers can be reversed without problem because they have auto-reversing systems in the wheel hubs that enable the brakes to collapse when rearward motion is instigated. Cars do not have such systems. The DfT information sheet states: From 1 October 1988 the inertia braking system was required to allow the trailer to be reversed by the towing vehicle without imposing a sustained drag and such devices used for this purpose must engage and disengage automatically. This will be very difficult to achieve on an A-frame using an inertia (overrun) device.

Some inertia-braked A-frame suppliers claim testing has proved their system meets the necessary braking force regulations and argue that cars on inertia-braked A-frames can be reversed without the need to manually operate any mechanism. One supplier says: It takes a little skill, but with care, gentle reversing can be successfully achieved.

In the past few years some A-frame suppliers have implemented designs to operate the car’s braking systems, including the power assistance system using electrical power from the towing motorhome. Suppliers claim these electrical systems provide the required braking efficiency and allow trouble-free reversing as the car’s braking operation depends on the motorhome’s brakes.

To avoid all the above technical problems relating to braking requirements, some campers have argued the braking requirements for A-frame towing of cars can be avoided by using a lightweight micro car where the GVW does not exceed 750kg. The argument goes that with a GVW (including A-frame) of less than 750kg, the unit can be considered as an unbraked trailer. However, if a braking system is fitted then the regulations require all the brakes to operate correctly and the micro car will have brakes.

While the DfT has set out its interpretation of the regulations, it has declared it is unable to give an authoritive interpretation of the law as this is a matter for the courts to decide. As far as we are aware, no one has yet been taken court in the UK for towing a car using a braked A-frame. As there is no mandatory testing regime in place, it is down to individual manufacturers to ensure their products meet the statutory requirements. If you decide to purchase an A-frame it would be wise to seek written assurance from your supplier that it complies with the regulations as laid out by the DfT.

If you do go down the A-frame route, check your car can be towed. Some cars, especially automatics, can have their transmission system damaged by being towed. Also inform your insurance company for both the car and your motorhome and check it is happy with the arrangements, especially if you intend to use the outfit outside the UK. And remember, reversing with a small towed trailer is notoriously difficult, especially when it is out of sight. Using a rear view camera can be helpful. Such cameras are now readily available as an aftermarket accessory.