by Martin Phippard


The first B double was introduced in Western Australia in 1981, The vehicle was operated by Wills Transtar and was 17.5 metres in length and consisted on two tandem axle semi trailers towed by a Mack slimline cabover prime mover. This was eventually allowed to increase the length to 18 metres in 1983 then to 19 metres in 1984 by including a triaxle group on the “A” trailer. The Temples B double in your photo was the second B double introduced in 1984. (Thank you Ian Tarling [Former Heavy Vehicle Operations Manager Main Roads WA] for this information.)

Another early WA B-double was the bulk pneumatic combination operated by Brambles-Manford and introduced in 1988. This is thought to have been the first example of a pneumatic B-double in WA.

Australia - as most truck people will know - approved the use of multi-trailer roadtrain combinations beginning in the1930s and when legislation was finally introduced in the late 1960s the largest of these could reach out to 50-metres in length and were theoretically capable of grossing somewhere between 115 and 137-tonnes. These leviathans pounded the dirt roads of the outback during the period covering the 1970s and ‘80s. Today’s combinations are even longer and heavier, so it would reasonable to assume that a comparatively modest twin-trailer combination would have been easily assimilated into the existing legislation. Yet while other countries were quick to recognize the advantages offered by the B-Train and rapidly adopted the configuration, Australia’s various state authorities were extremely hesitant to accept the idea and the B-Train was not seen in anything but miniscule numbers on the highway network of Australia until the mid 1980s.

Known initially as Multi-Trailer-Combinations (MTCs) B-Trains eventually became known as B-Doubles in Australia largely so that the legislators could avoid the emotive term “train.”

I am not certain which state allowed the use of the first B-Double in Australia but as may be expected, the more densely populated Southeastern areas were most reluctant to accept the new idea, fearing an unwelcome backlash from the general public.

In Western Australia what is thought to be the first bulk pneumatic B-Double was operated by Brambles-Manford in the colours of Cockburn Cement in 1988. Headed up by a twin-steer, tandem-drive Volvo F12, the Kockum’s Industries bulk tanks were configured with a long tri-axle lead tank and a short tandem-axle rear. The combination provided a net payload capacity of 41-tonnes and handling was reported by drivers to be better than a rigid eight-wheeler pulling a four-axle dog (drawbar) trailer.

Various Western Australian B-Doubles hauled behind 8x4 Volvo Tractors
Temples Volvo F-Model

Lindsay Brothers of Coff’s Harbour in Victoria launched their first B-Double, this being a curtain-sider hauled behind a Kenworth K-100E cabover. Power was provided by a Cummins N14 rated at 444-hp and this was transmitted to Rockwell SSHD rear ends via an Eaton/Fuller RTO 15618 gearbox. Suspension on the KW was the TBB-115 Torsion Bar rated at 20-tonnes capacity. Overall length was 23-metres and unusually for the period, the lead trailer was slightly longer than the rear.

Lindsay Bros. KW K-100E Reefer outfit

The ability to innovate has always been a basic requirement in the trucking industry and the Australians have always been particularly adept in this area. A case in point concerns a small livestock hauling company called Stockmaster from Tamworth in NSW. Established initially to improve efficiencies in their own operation, the company went on to design a B-Double stock crate (livestock carrier) featuring a short 6-metre (20foot) lead trailer and a 12.2-metre (40-foot) rear unit. During this period of evolution, B-Double trailers of anything but equal length were unusual enough, but what made the Stockmaster combination stand out even more was that the lead trailer featured tandem axles while the longer trailer was supported on a tri-axle group. While this made perfect sense from the point of view of payload the real, but less obvious advantage was that the longer, tri-axle rear trailer could be used behind a regular 6x4 tractor for everyday artic work.

The unusual trailer set was built by Mick Byrne (later Byrne Trailers) of Wagga and could carry two decks of cattle or four decks of sheep. Measuring 23-metres (75-feet six inches) overall and capable of grossing 59-tonnes, payload was in excess of 31-tonnes when the combination was coupled to a Kenworth K-100E 6x4 tractor. The idea of using trailers of different lengths later became widely accepted and is now commonplace in B-Double trailer sets throughout Australia.

A report appearing in the August 1991 edition of the greatly respected Australian publication Truck and Bus Transportation announced, with some frustration, that B-Doubles had finally been granted authority to operate on the Hume Highway connecting Melbourne and Sydney.

The report comments on the "years of hard work and intense lobbying" put in by the State of Victoria’s transport operators and the "equal number of years of bureaucratic back-pedalling by the Victorian government." Apparently dozens of applications for B-Double authority had been repeatedly refused transport operators. But on June 29, 1991, history was made when a Refrigerated Roadways B-Double was allowed interim approval to operate on the Hume.

KW fuel and bulk cement B-Doubles

"It seems incongruous that Victoria was the first State on the Eastern Seaboard to grant a (temporary) B-Double permit to operator Murray-Gouldburn in 1984, but that a general appreciation of the efficiency gains possible with B-Doubles has yet to be fully recognized," continued the report. What does seem particularly odd now is just how successful the B-Double has since become in such a wide variety of applications in Australia. Certainly one can sympathise with those operators convinced of the merits of the B-Double, but unable to take advantage of the extra capacity and revenue because of stubborn and short-sighted politicians. But what else is new?

It was not until 1992 that the first Federal B-Double Authority was granted to Kalari Transport Services. This was for an eight-axle bulk flour combination carrying cereals for Bunge Products of Altona (Melbourne) and was headed up by a Kenworth K-100E tractor unit.

At about the same time Universal Transport Operations (UTO) - formerly Townsville Transport – was adding Freightliner tractor units to its fleet, these being specified for use with what I believe to be an entirely new concept in B-Double trailers. The Freightliners were powered by a Cummins N14 Celect rated at 460-hp and were built on a short (4050mm) wheelbase. Meanwhile the trailer set was made up of a six-metre (20-foot) dry freight curtainsider coupled to a 12.5-metre (41-foot) refrigerated van. Both trailers were equipped with BPW air suspension and Yokohama tyres.

Shell Tanker Shell Tanker Rear View Argosy Curtainsider
Volvo Container Outfit Scania Tanker

While the Australians may have been slow in introducing the B-Train, they certainly accelerated into the fast lane when it came to exploiting the full potential of the concept. One of the first such developments was the introduction of the “Double B-Double” a four-trailer combination which, as its name suggests, was made up of two B-Trains (or B-Doubles) hooked together by a dolly converter. These impressive combinations were often hauled behind four or even five-axle tri-drive tractors and were popular with companies engaged in hauling bulk solids such as ore concentrate. Among the many companies quick to embrace the new technology and higher weights afforded by these combinations was Giacci Bros. of Perth who used unique twin-steer, tri-drive Volvo FH 16 cabovers to head up their 175-tonne outfits.

Old Giacci Body Truck plus double B-Double New Giacci Drom Tractor plus double B-Double outfit

Australian oil companies BP and Shell adopted the B-Double concept as soon as it was approved by the various state authorities in which they worked but were obliged to ensure that the new combinations conformed to exacting legislative standards. These included a minimum power-to-weight requirement, anti-lock braking, speed limiters, spray suppression material, Long Vehicle marker boards and specially qualified drivers.

In the early 1990s when new legislation introduced in the Northern Territory and Western Australia witnessed the possibility of roadtrains extending to 53.5-metres overall length and weighing up to almost 200-tonnes, these same oil companies looked a new ways in which to take full advantage of the larger combinations. One new configuration to emerge was the “2AB Quad” a four-trailer combination comprising two regular A-Trailers hooked together via a dolly converter plus a B-Double. Interestingly Shell configured their 2ABs by locating the B-Double at the front while BP hooked theirs to the rear of the A-Trailers. Other companies put the B-Double between the two semi trailers.

KW Shell 2AB Outfit BP Volvo NH 2AB outfit at Alice

One of the biggest roadtrains operated in Australia in the 1990s was a six-trailer combination configured as a "3B". This outfit, made up of three short B-Doubles, operated in a remote area of the Northern Territory and was hauled behind a tri-drive Western Star. However, problems with stability eventually saw this configuration abandoned in favour of a B-Triple coupled to a B-Double.

Hampton outfit. B-Double plus B-Triple

The B-Triple is a three-trailer combination hooked together in the same way as a B-Double, but incorporating two trailer-mounted fifth wheels rather than one. These interesting and undeniably impressive combinations have one huge advantage over standard outback three-trailer roadtrains and that is simply that from a legislative standpoint they are regarded as “Long Vehicles.” This quirk in Australian road transport law means that although a B-Triple combination can stretch out to 35-metres overall and is almost as productive, if not as versatile as a three-trailer roadtrain, the stigma that is invariably associated with the word “train” is conveniently avoided. Consequently one finds B-Triples employed in an ever-increasing range of duties including not only curtainsiders and platforms but also livestock crates, tankers and even tippers.

Linfox Freightliner Argosy B-Triple Ford Motor Company of Australia Curtainsider B-Triple
Used with permission

These photos were added on September 13, 2008

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