Need for Better Handbrakes
Page 34
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BY A SPECIAL CORRESPONDENT
IT was quite easy to foresee that as soon as periodic tests were instituted for light commercial vehicles and private cars—with the tests having to be -undertaken by private garages, and not at official stations—a minimum standard of
brake performance would have to be laid down. These requirements were listed in the sixth schedule of the Motor Vehicle (C. and U.) (Amendment) Regulations, 1960, S.I.1065, paragraph 4, as follows: in the case of a motor vehicle having at least four wheels and required to have two means of operating brakes,
(a) if each means of operation applies brakes to at least four wheels, the
brakes as applied by one of the means shall have a total braking efficiency of not less than 50 per cent, and the brakes as applied by the other means shall have a total braking efficiency of not less than 25 per cent; (b) if only one of the means of operation applies brakes to at least four wheels, the brakes as applied by that means shall have a total braking efficiency of not less than 50 per cent, and the brakes as applied by the other means shall have a total braking efficiency _ of not less than 25 per cent; (c) if neither means of operation applies brakes to at least four wheels, the brakes as applied by one of the means shall have a total braking efficiency of not less than 30 per cent, and the brakes as applied by the other means shall have a total braking efficiency of not less than 25 per cent.
The schedule in paragraph I laid down that it did not apply to goods vehicles exceeding 30 cwt. unladen, p.s.v. adapted
to carry eight or more passengers, and articulated vehicles ot._..a vehicle cm-.
structed or adapted for, the purpose of
forming part of an articulated. vehicle. This meant that, it applied, only . to.
vehicles required tt) be Periodically tested at that time.. Nevertheless, this was•the first time that any, standard had. been laid down. _ Since the introduction of C. and U. Regulations, the braking requirements have never been specific and generally require that a motor vehicle be fitted with two means of brake operation, each to be capable' of stopping the vehicle within a reasonable. distance under the most adverse conditions.
Despite the legal requirements, many manufacturers of heavy commercial vehicles have used a design of handbrake that can be regarded only as a holding device. Operators feared that once a minimum standard braking standard had been laid down for only a limited class of motor vehicle, the police and vehicle examiners would be inclined to adopt the standard for other vehicles, at least as a basis for spot checking. Fortunately, this does not appear to have happened so far, although at intermittent intervals various police forces indulge in a spate of prosecutions of commercial vehicle operators for having vehicles with inefficient brakes—op the grounds that the handbrake will not stop the vehicle within "a reasonable distance".
I do not believe this could occur in any other country, but here we have manufacturers producing vehicles which do not comply with the (admittedly vague) legal requirements—yet it is the user who has to bear the brunt of any prosecutions This position has often been brought to the attention of commercial vehicle manufacturers, but without noticeable effect so far as many are concerned.
In 1953 the Department of Scientific and Industrial Research, Road Research Laboratory, issued a technical paper called "The Braking Performance of Motor Vehicles and Brake Testing" (No. 26). In a section, "Braking with the Handbrake ", it stated:
" There are differences of opinion on the function of the handbrake; some consider it is an emergency brake, others regard it as a holding device. The fact remains, however, that the law requires a vehicle to be fitted with two means of brake operation, each of which must be capable of stopping the vehicle: within a reasonable distance. In some makes of car, the handbrake operates on all four wheels and the deceleration attainable is much less than with the footbrake. In many of the heavier vehicles, the design of the handbrake system is such that it can only be regarded as a holding device".
In the section on " Minimum Braking Requirements-' it • stated: --•• _ "The law requires that the handbrake should be capable of stopping the vehicle in a reasonable distance, but the design of some handbrakes is such that they can only be regarded as a holding device. Results obtained on vehicles in use show that there would be a marked improvement in the present standard of handbrake performance if all vehicle handbrakes could produce a maximum deceleration of at least 0-25 g ".
Yet looking at road test reports published recently, it is still apparent that the handbrakes of many new commercial vehicles cannot meet the recommended minimum requirements.
It is only a question of time, in view of the reports of the Licensing Authorities, before there must be an improvement in the general maintenance and braking standards for commercial vehicles, and this will be obtained—as has already been announced—by extending the classes of vehicles subject to periodic tests, When the heavier vehicles are included, the operator will be regularly vulnerable to prosecution and to " stop " notices in respect of most of his heavy vehicles and there will be little he can do about it.
How can the ordinary law-abiding commercial vehicle operator safeguard himself? It is possible that the Continental manufacturer is prepared to provide a vehicle which will comply with the legal requirements of this country—one has only to visit the Continent to see diesel vehicles that do not emit black smoke whilst doing the work for which they are sold.
Surely the operator should be able to rely on his trade association to act as a pressure group to make the manufacturers produce vehicles which can be operated with complete legality in this country? .