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Standardisation will open new opportunities

While the owner-driver concept has made significant inroads in South Africa, the modus operandi of the top-end of this new breed, namely owner-drivers with their own truck tractor, remains a far cry from the concept as practised in overseas countries - particularly in America. There the owner driver is a freelance operator who can haul anybody's semi-trailers. In South Africa, our owners drivers are generally restricted to contracting to single large operators. Why is this? Jack Webster, FleetWatch's correspondent on legislation, outlines the complexities of the issue and it all revolves around the semi-trailer and its compatibility with the truck-tractor.

In order to fully examine this issue, it is necessary to explain the actual status of the semi-trailer in South Africa. In the December 1998 issue of FleetWatch, Dave Scott presented a true but dismal picture of the standard of maintenance of trailers - including semi-trailers - in South Africa. But let it not be misunderstood - South Africa is not alone with the problem.

The November 1998 issue of "Transport Engineer", the UK monthly mouthpiece of the Institute of Road Transport Engineers, includes an interesting article by the deputy editor, David Wilcox, titled Putting a Stop to Trailer Test Failure.

Based on information obtained from the Ministry of Transport Vehicle Inspectorate, Wilcox reveals that 25% of all trailers four years old or younger, fail the first time at the annual inspection test and the main reason given is "lack of or bad maintenance" with emphasis on failure to meet minimum brake performance.

But Britain is more fortunate than South Africa. At least they pick up the problems at the vehicle testing stations and refuse to 'pass' the vehicles. This raises a most interesting aspect of the method of testing vehicle brakes, briefly mentioned by Dave Scott and more emphatically by David Wilcox, and also receiving the attention of our own Road Transport Operators' Technical Committee.

Compatibility never checked

The compatibility between the brakes on trailers and semi-trailers and the brakes on the drawing vehicles are never checked. Each vehicle of a combination is tested individually on the brake roller tester and both may pass the test. However, in terms of compatibility, they are dangerously far apart. In fact, in South Africa they may be miles apart given that operators are coupling brand new state-of-the-art truck tractors with ancient semi's.

Take as an example the six-axle articulated vehicle, the 6 x 4 truck-tractor fitted with ABS (anti-lock) disc brakes producing maximum brake performance. This is coupled to a ten year old semi-trailer with no more than a twin-line braking system, cam brakes and no slack adjusters. Both vehicles, having passed the brake test in the unladen condition, have valid certificates of roadworthiness but the compatibility of the systems has gone unchecked.

Now say the driver, travelling at 80 km/h laden to a gross mass of 46 tons, has cause to apply full power of the service brake - the truck-tractor responds and the brakes of the truck-tractor are applied. However, the semi-trailer brake system responds but the braking performance had not been checked in the laden condition. The ultimate result is inevitable. A jack-knife and serious accident. Of course, the accident report will include the usual "cause of accident" as being semi-trailer brakes failed!

The truth is - to test the brakes of vehicles as separate (individual) vehicles and then expect compliance with regulation 287(1)(a)(i) when the vehicles are part of a combination of vehicles is almost impossible. This Regulation states:

"Braking performance of service, emergency and parking brakes

287. (1) No person shall operate on a public road a motor vehicle or a combination of motor vehicles which, in terms of these regulations:

1. shall be equipped with a service brake, unless such brake at all times:

(i) in the case of a motor vehicle or a combination of motor vehicles which is capable of exceeding a speed of 35 kilometres per hour, when it is applied from an initial speed of 35 kilometres per hour, complies with the requirements for braking performance set out in Table A.

The Regulation is clear:

(c) The brake performance must achieve a maximum stopping distance of 16 m (heavy motor vehicle) from an initial speed of 35 km/h".

This regulation has been there in principle since the first Road Traffic Regulations were introduced in 1957 and ever since it has been argued that testing vehicle brakes on a brake roller tester - with the vehicle unladen - may serve some purpose. However, it is not the complete answer.

Over 40 years ago, four-wheel two-axle trailers with brakes on the rear axle only passed the test on brake roller testers. However, when put through a road test, they failed miserably due to the influence of dynamic braking and mass transfer due to retardation. The persistent appeals that the annual brake test on heavy goods vehicles and buses should include a road test, particularly in the case of combinations of vehicles, using the drawn vehicle as the vehicle being tested coupled to a suitable drawing vehicle, have been rejected because of the wording of Regulation 287(2)(b) which states:

"(2) Compliance with the requirements contemplated in sub-regulation (1)(a) and (b) shall be determined by:

(a) actual road tests conducted on a road with a reasonable level, dry, smooth and hard surface which is free from loose material and with the stopping distance measured from the moment the particular brake is applied with the engine disengaged until the vehicle comes to rest; or

(b) a suitable mechanical test; or

(c) both tests contemplated in paragraphs (a) and (b)".

Because of the use of the word "OR" between paragraphs (a) and (b), they do not accept the alternative (b) which means there is no check on the compatibility of the brakes of drawing vehicles and drawn vehicles in combinations of vehicles.

There are many other areas of concern about the maintenance, road worthiness and geriatric age of our trailers and semi-trailers but has thought ever been given to the reasons why, semi-trailers in particular, have not received the care and attention to which they are entitled?

The answer is not difficult to find. Neither Britain nor South Africa have really accepted the articulated vehicle for the purpose and use intended as is the case in countries such as the USA, Canada and Germany and other countries in Europe.

In South Africa, orders are placed for truck-tractors and semi-trailers as coupled units and are only uncoupled when the truck-tractor is serviced and presented for the annual C.o.R. test. During these times, the semi-trailer is parked in the yard and no thought is given to routine regular service.

Additional problems

This marrying of a truck-tractor to a semi-trailer creates additional problems which have existed in South Africa since the articulated vehicle arrived in South Africa after the Second World War. Standardisation of essential dimensions hardly exists between depots of a company let alone on a national level.

There is no standard prescribed dimension for fifth-wheel height whereas in the USA, irrespective of make or model of truck-tractor, the height of the fifth-wheel is 52 inches (1 320 mm) on a 6 x 4 and 49 inches (1 244 mm) on a 4 x 2. Other essential dimensions such as air and electrical connections are all standard and any 6 x 4 truck-tractor can couple to any two or three axle semi. The same applies to 4 x 2 truck-tractors and suitable semis. What this does is it opens the door for the genuine freelance owner-drivers of truck-tractors to offer a service to all larger operators who own fleets of semi's but outsource their truck-tractor requirements.

I put it forward that the lack of standardisation of essential dimensions and the inability to interchange truck-tractors and semi-trailers, even within a fleet, costs South Africa dearly in terms of vehicle utilisation and flexibility.

It is interesting and relevant to mention that in February 1986, the IRTE in London produced a Code of Practice for truck specifications in connection with coupling dimensions and interchangeability between truck-tractors and semi-trailers. The IRTE code refers to an ISO Code No 1726 which was alleged to be out-of-date in 1986 and was about to be updated. Enquiries are being made through the SABS for any updates to ISO 1726 and also to IRTE, London, for any updates to the IRTE code.

A door of opportunity

Get the standardisation and compatibility right and you will then open another door of opportunity, namely, a sector which could provide semi-trailers on a rental basis.

Over 25 years ago, an effort was made by Rentco to get this going. Rentco was a subsidiary of Henred Fruehauf which was named after the division of Fruehauf Trailers in America with the same name. However, while the American Rentco was a successful operation, the South African company failed. Why?

The answer becomes obvious when one considers what has been said about the lack of standardisation of essential dimensions, lack of compatibility of brakes, etc. Put these things right and, equally important, make essential dimensions of truck-tractors subject to mandatory standards, and the concept of making available a comprehensive range of semi-trailers for rental will enjoy the same success as it has overseas.

Come on SABS, RTOTC, RFA and IRTE! We have the ability and the know-how. In the interests of the industry - and certainly in the interests of the new breed of owner-drivers - let us go for it!

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