The WHYS and WHEREFORES of B-TRAIN COMBINATIONS

by Martin Phippard

The big advantage of the B-Train configuration is its inherent stability when compared to other twin trailer combinations and it is this feature above all else that has ensured its continued development and global acceptance. Relatively little research into the origins and evolution of the concept is apparent and perhaps surprisingly there are still some countries where the advantages of the B-Train have been neither recognized nor exploited.

Although known as a B-Train in several countries, this particular twin-trailer combination is also known by the term Interlink in South Africa and as a B-Double in Australia. I have been fascinated by this particular configuration since I first got to drive one (a tanker combination in Canada headed up by a GMC Astro SS) in 1978 and have since driven examples in Sweden (Volvo F12 plus gull-wing curtainsiders) where they are relatively rare, in Zimbabwe (Scania 112E curtainsider) when I made a run to Beira in Mozambique in 1987 and in Holland where I had a very brief spell recently at the wheel of the Scania 4-Series that heads up the famous KOV Combination B-Train.

Before embarking on the history of the B-Train, it may be prudent to examine the terminology used to describe it and other twin-trailer combinations. An excerpt from a U.S. DoT document published in 1997 reads as follows:

"The common double configuration is called an A-Train. It is similar to a regular tractor/semi-trailer combination with a following full trailer. The ‘full’ trailer is usually composed of a single or double-axle dolly (‘A’ dolly) that has a drawbar that connects to the rear of the first semi-trailer and has a fifth wheel mount for the second semi-trailer. The drawbar of the dolly is usually fitted with a pintle ‘eye’ that connects to the pintle ‘hook’ which is mounted at the rear of the first semi-trailer. A second semi-trailer is hitched to the dolly-mounted fifth wheel. Brake and electrical lines join the two trailers.

International A-Train taken in Israel	American A-Train - USF Reddaway Ford

A Western double (U.S.) is an A-Train with two equal-length (up to 28-feet) trailers with an overall length of 65 to 68-feet (20 to 21-metres). In Canada the maximum length is 25-metres. Turnpike double is a U.S. term for a combination composed of a tractor and two 45-feet long trailers. These are used in the Western United States and on some Eastern toll roads (e.g. The New York Thruway and Florida Turnpike). Another combination is called a Rocky Mountain double and this is a tractor with both a 45-feet trailer and a 27/28-feet trailer. These, as the name suggests, are used in the Western U.S. States.

International DCO-405 with Doubles	Brockway Turnpike Doubles	Canadian Freightways Rocky Mountain Doubles

A B-Train has a special lead trailer with a rear-mounted fifth wheel. The B-Train is favored by Canadian regulations because of its increased dynamic stability and higher payloads for the same overall length. The second trailer is coupled to the fifth wheel at the rear of the first trailer. B-Trains have more yaw stability and roll coupling (stability) than others. B-Trains are allowed higher loads in Canada. B-Trains are usually special-purpose machines that remain together as a pair.

B-Train Slide (Canadian) KW 900 plus loaded lumber train

The C-Train is similar to an A-Train except that two drawbars are used to eliminate the freedom to rotate about a vertical axis at the hitch point. The dolly is equipped with self-centering, self-steering axle(s) that require a side force of about 0.3g to steer. Canadian regulations allow slightly higher loads on C-Trains than on A-Trains."

Detail of C-Train hook-up by Univision of Biggar, Sask.	Mexican KW T800 plus C-Train Vans in mountains	Freightliner and C-Train chip vans from Longview, WA. filmed in Morton, WA. in 1990

As may be seen from the above, even the U.S. DoT struggles to define with absolute clarity the various configurations used regularly within its own home territory. And there is no attempt to elaborate on the various differing types and styles of B-Train combination in use. However, these areas will be more fully explored in the following pages.

It is widely, though it seems mistakenly assumed, that B-Trains originated in Canada. In fact in New Zealand where the configuration has been in regular use for about 20-years, the combinations were frequently referred to as “Canadian-style doubles” or “Canadian-style B-Trains” when they first started to appear on that country’s roads.

In the late 1970s the Canadian trucking monthly, Motor Truck, ran an appeal asking operators and manufacturers who had used the earliest B-Trains. The result was revealing in that many operators who had used B-Trains for only a short time thought that theirs was probably the first. In fact the only real evidence of B-Trains prior to the 1970s was supplied by Arrow Transfer of B.C. who said they first employed the concept in 1967. However, Tank Truck Transport (thought to be from Sudbury, Ontario) claimed to operate a twin tank B-Train built by Fruehauf Canada hauling acid for the International Nickel Company in the mid 1950s, but regrettably could not provide photos or documentary evidence to support this. But at the time this unsubstantiated claim certainly suggested that it was the first known example.

In fact a long way south of Canada in sunny California Dan Keeney had unknowingly beaten everyone to the punch. Dan had started out on his truck-driving career back in 1933. But following an accident in 1936, he went to work for International Harvester as a truck salesman, a task he carried out with great success for the following eight years. But the call of the open road was ever present and in 1944 he could resist the temptation no longer and left IH in order to start up his own company, Keeney Truck Lines. By 1947 he had gone on to design and build his own twin-trailer combination by fitting a fifth wheel at the back of the first trailer. In this way he built and later operated what would seem to be the earliest example of a B-Train recorded anywhere.

Keeney B-Train International Photos

By 1953 six similar B-Trains were in use, these having been built by the now defunct Foster Trailer Company of Los Angeles. The combinations were only ever used in California and it was almost 40-years later that Dan’s son, Walt Keeney, reintroduced B-trains to the Keeney operation. The first of these was used for hauling flour and was operated throughout Washington State. During the mid 1990s, it was my great privilege to meet Dan Kenney and his son, Walt at the Morton, WA. Loggers’ Jamboree and later to film a Keeney B-train tanker combination hauled by a conventional Freightliner.

Walt Keeney Freightliner COE plus tanks

British Columbia, Canada’s most Westerly province, witnessed the introduction of several interesting examples during this period and trailer sets ranged from flat decks to tanks and even included dual-purpose ‘platypus’ trailers which covered both modes of transport. In the East too transport companies in Ontario and Quebec were cautiously introducing B-Trains to their fleets of tankers and flat decks.

BC Outfits
Labatt’s Freightliner	KW W-900 with load of lumber
Fern Cote Freightliner Powerliner	Dave Chambers Trucking Mack Ultraliner and set Chip Vans

The Michigan rigs of the period were certainly extremely visually appealing, the biggest rolling on 11-axles in total, grossing up to 160,000-lbs (72.2-tonnes) and rolling behind exotic breeds such as Brockway, Diamond-Reo, Hendrickson and Peterbilt, even the latter marque being virtually unknown in Eastern Canada at the time. But Canada’s seven and eight axle combinations were not far behind with the biggest grossing 140,000-lbs or 63.5-tonnes. What is still unclear is why Canada and Canadian truckers have adopted the B-Train for almost every type of load whereas in the USA, the concept seems limited almost exclusively to Michigan State.

Michigan Peterbilt 352 cabover steel-hauling outfits

Freightliner conventional	Freightliner COE at Scales	Freightliner conventional by piles of wood chips

As acceptance by authorities, operators and drivers increased, so the applications in which B-Trains could be used expanded. However, this did not mean that they suited every job. For example boxvan trailers were nearly always hooked up via a dolly converter in A-Train configuration because it was usually necessary for them to be backed up against loading bays. This was impossible with the lead trailer in a B-Train set because the tail section was in the way. So trailer manufacturers quickly developed a mechanism that allowed the tail section to be retracted under the floor for loading and unloading and this system inevitably became known as the ‘goodbye dolly’. But such systems are, by necessity, both complex and costly. The principle of the B-Train has, however, maintained its popularity with tank operators, steel and lumber haulers – for reasons of stability – with mid-Western grain haulers and wood-residual haulers everywhere who like to utilize every last cubic centimetre of capacity!

Home Hardware Sliding Bogie Vans.

The wood residuals business is an important part of Canada’s economy and truck operators engaged in hauling these products use some of the most sophisticated B-Trains to be found anywhere. For more than a decade operators such as Trimac, Arrow Transportation and Dave Chambers Trucking have operated high-volume B-Train sets which not only handle safely in the mountains but which squeeze every gram of payload aboard. A special feature of these combinations is that when unloading the two trailers form a single unit which allows the second to tip its load through the first. It’s a slick system and light years ahead of A-Train systems used in Washington State where each trailer is unloaded separately. Needless to say, chip haulers in Washington State look Northwards to Canada with a degree of professional jealousy as they watch Canadian operators haul higher weights in more stable twin-trailer combinations that can be unloaded in one hit!

Gold Star Trucking Mack and bulk chip vans from Peace River	Maritime Provinces Volvo VN-660 and Chip Vans.

While the development and refinement of B-Trains continued cross Canada and in a few isolated parts of the United States through the 1970s and early 1980s, other countries around the world started to sit up and take an interest in the idea of the B-Train. In South Africa the concept was introduced as the ‘interlink’ and indications are that the earliest examples were built in 1981 by the South African trailer manufacturer Henred-Fruehauf. These fairly basic combinations were built for Norman’s Van Lines and used for the transportation of bottled drinks. A year or two later other trailer builders including Busaf Industries from the Transvaal and CI Trailmobile launched their versions of platform interlinks suitable for carrying either deck-loads or two 20-feet containers. Permitted overall length of interlink combinations behind a 6x4 cabover tractor at the time was 20-metres (65-feet 8-inches) and maximum gross weight limited to 47-tonnes.

One combination of particular interest was that designed by Stuttaford Van Lines of Cape Town for long distance furniture moves. The combination consisted of two drop-frame box vans of equal length, the first having a tandem-axle set up and the rear a single axle. The rearmost trailer was equipped with a small crew area containing cooking and washing facilities. The combination was hauled by British Foden 4000-series single drive tractor unit which, because of local legislation at that time, was powered by a South African-built diesel known as an ADE 422T and driven through a locally-built Astas 16S190 gearbox (a licence-built ZF). An increase in volume of 25% was claimed for this interlink when compared to earlier doubles combinations

South African Interlinks

Beginning in 1990, interlinks operating in South Africa could extend to 22-metres (72-feet) overall and gross 56-tonnes on eight axles with a small tolerance on gross weight of about three tonnes provided individual axles or axle groups were not overloaded. Current interlink trailer sets include platforms, curtainsiders, tanks, skeletal container carriers, fridges and even furniture vans.

The most advanced interlinks in use are without doubt the dual-purpose ‘platypus’ units known as General Freight Liquid Tankers or GFLTs. Designed and developed by Peter Bennetto of Cargo Carriers, these all-aluminium trailer sets offer significant advantages in the crucial areas of stability, payload, safety and versatility yet are rugged enough to operate in countries adjacent to South Africa where road systems are not necessarily as well developed. They were introduced to haul fuel from South African ports to land-locked countries and then deck loads such as sugar or timber on the return trip. .

GFLT Interlink with deck load

One of the first was Ian Strachan from Harare whose early interlinks were almost certainly over-engineered and which, interestingly, featured a tri-axle bogie at the rear rather than in the centre, beneath the fifth wheel, as is more customary today.

Ian Strachan NET Tank Interlinks behind Foden tractor

Subsequent Strachan interlinks, operated in the fleet colours of NET, were built primarily to haul fuel from the port of Beira in Mozambique into land-locked Zimbabwe. The trailer sets were essentially ‘skeletal’ trailers designed to accommodate demountable fuel tanks or even three 20-feet ISO containers. Measuring 22-metres overall, the rugged interlinks were built by More-Wear Equipment of Harare (previously Salisbury). Tractor units (still referred to as ‘horses’ in Zimbabwe) used at the front end of the interlinks were either British-built units from ERF, Foden or Scammell or Europeans Mercedes and Scania. All of these heavy-duty units were modified to accept long-range fuel tanks mounted vertically behind the cab and featured impressive Australian-style bull-bars and stone-guards.

Strachan Foden Container Rig	Scania B-Train curtainsiders operated by Kimon Raftopolous of Harare

Unfortunately, due to travel restrictions imposed in recent years, little is known about Zimbabwe’s internal transport system at present. However, a visit to Beitbridge on the busy Zimbabwe/South Africa border in 2000 showed that the interlink system is still the most popular configuration for long-haul work although, because labour is cheap, platform trailers are often used rather than curtainsiders. Legislation dictates that combinations do not exceed 22-metres in overall length and weights are limited to 55-tonnes gross mass.

Many other countries in Southern and Central Africa including Mozambique, Botswana, Tanzania, Angola and Zambia also use interlink systems and as far back as 1986 Henred-Fruehauf Trailers in South Africa were building six-axle tri-tri interlinks for White Horse Carriers in Botswana. These were heavy-duty platforms designed to haul trailers northwards into Zaire and return with deck loads of zinc slabs. These combinations were hauled by Scania 142E tractors fitted with 2,000-litre (440-gallon) long-range fuel tanks.

CURTAINSIDER/TANK Mercedes. These trailers were actually tankers disguised as curtainsiders to discourage high-jackers.

Two other neighbouring countries, which have used B-Trains extensively, are New Zealand and Australia. However, despite the fact that Australia had accepted the need for multi-trailer Roadtrains for outback operations since the 1960s and – it could be reasonably assumed – would readily accommodate B-Trains into the transport legislation, it was in fact New Zealand that first embraced the B-Train concept.

Mack Ultraliner	International F4870 logger
Mack Superliner	IH T2670 curtainsider
Leyland/Scammell S26	Foden 4000 series
Scania 142 Tanker	Volvo F12 Tanker
Renault G-Series Tanker	Scammell S-26 load lumber

Like most other countries having B-Trains, those found in New Zealand are primarily platforms, curtain-siders and tanks. The earliest examples appear to have been platforms and grain bulkers, these emerging in the late 1970s. Among the earliest examples were the two outfits operated by Katway Haulage of Auckland on a soft drinks contract. Headed up by impressive 6x4 Kenworth Aerodyne tractors, they were configured with two trailers of similar length, each riding on tandem axles. A similar combination was used by the Kaitaia Timber Company to haul lengths of sawn timber behind a rugged Mack Superliner while a splendid, green-liveried Kenworth K-124 sleeper operated by F.J. Ramsey was used to carry wooden fencing posts. Some idea of how new the B-Train concept was to New Zealand’s truckers at this time can be gathered from the fact that Ramsey’s KW combination was referred to as a “unique semi-trailer on a semi-trailer unit”. But whatever they lacked in their knowledge of terminology, the Kiwis quickly made up for in sheer ingenuity and by the mid 1980s it was possible to see a wide variety of B-Trains in use, these being hauled by tractor units from manufacturers in Britain, Europe, North America and even Japan.

But the biggest single business in N.Z. is logging and it was not long before Kiwi B-Trains designed specifically to haul logs were introduced. This seems natural enough now, but it is worth remembering that at the time, B-Train logging sets were virtually unknown. A few isolated examples such as those operated by Doyle’s Transport of Paris, Michigan surfaced during the early 1990s, and subsequently B-Train logging trailers have become commonplace in Canada, Australia and South Africa. But New Zealand certainly appears to have been the country that started the trend and folding B-Trains such as those pioneered by operator Mike Lambert were almost certainly an industry first.

The latest B-Trains operating in New Zealand are undoubtedly sophisticated pieces of equipment featuring antilock brake systems and a wide variety of bodywork ranging from curtainsiders and bulkers to tanks, container skeletals and even livestock carriers. Maximum permitted weight is 45-tonnes and maximum overall length 20-metres. These days most trailer sets feature two tri-axle groups or a three-axle group beneath the coupling and a tandem axle group at the rear. A seven-axle combination is all that is required to carry the maximum weight but operators using eight axles pay a reduced Road User Tax.

Ford L Platform	Mitsubishi Vans
Volvo FH tarped load	Mack Curtainsider
Mack Superliner Curtainsider	Mack Ultraliner Curtainsider
Kenworth deck load lumber

Astonishingly, the country, which has done most in terms of developing the B-Train, was also one of the most hesitant to accept the idea initially.

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

In many ways legislation governing the operation of heavy trucks in Sweden is very similar to that in Canada. Maximum gross weights are limited to 60-tonnes and overall length for most combinations to 24-metres. However, the type of trucks operated is very different with most Swedish combinations comprising a rigid three-axle cabover coupled to a 12.8-metre (42-foot) full drawbar trailer.

There are two almost unbelievable aspects of Sweden’s road transport history that are worth mentioning. The first is that until 1967 all traffic drove on the left side of the road and one day in September of that year, changed to driving on the right as in the rest of mainland Europe. Second, until 1968 there was NO legislation governing truck operation, so operators simply hauled as much as their trucks could carry. Consequently the length of some combinations reached out as far as 35-metres (115-feet) and weights were often in the region of 70-tonnes despite the relatively modest power outputs of truck engines in that period.

Although there was obviously no legislative reason to operate a B-Train combination, it appears that numerous examples were put into service by Swedish truck operators for no other reason than the configuration made good sense in terms of vehicle stability and ease of operation. For example truck manufacturer, Volvo, operated B-Train platform trailer combinations capable of carrying four 20-foot containers behind one of its cabover tractors and there were several similar configurations in use at the same time.

Since 1968 few Swedish operators have elected to use B-Trains, most staying with the more traditional truck-trailer set up. In fact legislation in Sweden until the 1986 actively discouraged the use of any twin-trailer combinations by restricting their maximum speed to 40-kph (25-mph)! However, stability tests using a variety of twin-trailer outfits finally convinced the Swedish Department of Transport that B-Trains were at least as safe as truck-trailers and consequently a few have entered in recent years, most being designed to carry containers. Other interesting examples include the “paper trains” used to haul rolls of paper from the huge mill in Gruven to the inland port of Karlstad and a skeletal outfit configured to haul three demountable milk tanks from collection areas to large processing plants. More recently a Scania-hauled B-Train capable of hauling two 13.6-metre (46-foot) containers operates a regular service between the cities of Gothenburg and Stockholm, under special dispensation of course. In some respects it appears that the halcyon days prior to 1968 are being relived.

Volvo dual-purpose Platypus outfit	Container Outfit	Twin 45-footers behind Scania 4 x 2 tractor

OMT demount milk tanker with three demount tanks

Because road transport legislation governing overall length in the Netherlands conforms to that of the rest of mainland Europe, tractor-trailer combinations are limited to a maximum of 16.5-metres (54-feet) while truck-trailer combinations go a little longer at 18.35-metres (60-feet). However, it is clear that these dimensions are not ideal when it comes to the use of any type of twin trailer combination, and consequently B-Trains are almost unknown.

However, the road transport authorities in Holland have always been very forward thinking, and allow a certain amount of experimentation when it comes to new ideas. Consequently there is at least one B-train currently working in Holland, albeit on a trial basis, this being a 22-metre (72-feet) long combination operated by KOV Transport under special authority.

The KOV combination is unique for several reasons and combines technologies from various sources. It is designed exclusively for hauling containers in the area around Rotterdam docks. Consequently the rearmost section is made up of two trailers forming what is known as a “combi-trailer.” This is a five-axle trailer that looks like a regular semi-trailer but which splits in the middle. In this way two 20-foot containers or one 40-foot may be carried, and if necessary the trailer can be divided so that the 20-footers can be delivered to different destinations or backed on to separate loading bays. The combi-trailer is now finding favour with operators in Belgium and Britain too, but has its biggest following in Holland.

The KOV combination goes one better by having a short lead trailer capable of carrying one additional 20-foot container. This is fitted with a fifth wheel on to which the combi-trailer is coupled and in this way the outfit can carry three 20-foot boxes or one 20 and one 40-foot, all within an overall length of 72-feet. The KOV vehicle is restricted to working within a 50-km (30-mile) radius of Rotterdam docks when complete but when broken down in any of the three ways possible is free to roam anywhere in Holland or its neighbouring countries. Because the KOV vehicle has not been given an official designation I feel it is best described as a “Combination B-Train.”

KOV Combination B-Train

Despite the fact that legislation in France restricts all combinations to a maximum of 40-tonnes gross weight and lengths to 16.5-metres (54-feet) for tractor-trailers and 18.35-metres (60-feet) for truck-trailers there have been a few isolated attempts to run B-Trains during the past 20-years.

Most of these were unusual in that they were "convertible" combinations used to haul empty 20-foot containers before the advent of the combi-trailer. The B-Trains were assembled by using a special tandem-axle semi-trailer that converted to the lead section by virtue of an extendable rear bogie housing a fifth wheel. A second trailer could then be coupled to the fifth wheel of the lead trailer in the normal manner. Such systems, pioneered by Ackerman-Fruehauf of Germany in the mid 1980s did allow operators some flexibility, but in practical terms the constraints imposed by low weights and modest overall lengths did not offer much scope.

However, there have been unconfirmed reports in recent months that B-Trains hauling two 40-foot containers are working in the port area of Calais. Such combinations would be far in excess of the legal length limit, but may be operating under special dispensation. However, it should also be pointed out that several of the earlier B-Trains hauling containers in France certainly appeared to be far longer than the maximum overall lengths permitted for tractor-trailer combinations suggesting either that they enjoyed special dispensation or that they simply flouted a system that did not recognise the B-Train concept.

Renault B-Train	MAN B-Train
Scania B-Train	Iveco A-Train

In my opinion some of best looking B-Train combinations one can see anywhere are those hauling in Michigan State. Today these 11-axle outfits can legally scale at 164,500-lbs gross weight (74.78-tonnes) and because many are driven by owner-operators, the standard of finish is truly astonishing with polished Alcoa wheels and matching trailers the order of the day.

Various Michigan Break-Doubles

Michigan’s steel-hauling rigs are configured differently according to the size of coils they haul. For example, on the lead trailer of a typical 8-axle B-Train trailer set it is possible to see four, five or even six-axles under the fifth wheel tail with two, three and sometimes four-axles under the rear trailer. Axle groupings and spacings are described by the steel haulers in their own unique way. A “tandem-nine-quad-nine” describes a set-up in which there are two axles at the rear of the rear trailer, a single axle nine feet ahead, four axles under the tail section of the lead trailer and another single nine feet ahead. These descriptions always describe a sequence running from the rearmost axle forwards.

Tandem-Nine-Quad-Nine Photos

During the 1970s most steel haulers used flat decks or platform trailers and coils were tarp’d while in transit. Current coil carriers employ either hoop trailers or sliding-siders (curtainsiders) both of which allow faster turn-arounds. Although the current trailers are undeniably more efficient and driver-friendly than the platforms, it is debateable as to which actually looked better. A 1970s 11-axle B-Train headed up by a long hood conventional Brockway 762 and carrying several coils neatly sheeted in shiny black tarpaulins is a memory to cherish!

Doyle’s Autocar	KW Steel Coils
Mack Steel Coils	Ford Curtainsider

Despite the fact that that trucking dominates the transport scene in Brazil and that that double trailer combinations have been in use for over a decade, B-Trains were adopted only recently in 1999. However, these are some impressive combinations, the largest now being able to gross up to 90-tonnes and stretch out to 30-metres overall. I hope I will soon be able to post pictures of these Brazilian B-Trains on the webpage and regret that I am not able to do so at this point.

Regrettably the same situation exists with reference to Mexico except that in this instance I had no idea B-Trains were used there at all and discovered this fact only recently. I was certainly aware that Mexican legislation allowed the use of twin trailer combinations and had filmed the big C-Train box-vans operated by the Tecate Beer Company on several occasions. However, I have recently been informed that B-Trains” are now the favoured form of configuration for inter-city hauls” and that the idea is growing in popularity. Again, I regret that I am unable to include photos of Mexican B-Trains at this juncture but hope to add these to the web page in due course.

Today B-Trains continue to enjoy wide acceptance throughout Canada with lengths reaching out to 25-metres overall and weights generally grossing at 63.5-tonnes except in the Yukon where special dispensation allows some operators to gross as much as 72-tonnes with tri-drive tractors. They are used to haul virtually every sort of load although I have not yet found any evidence of livestock haulers using the B-Train configuration in Canada. Perhaps some enterprising livestock operator will visit Australia to see for himself just how successful B-Trains can prove in that application too. Meanwhile, we will have to content ourselves by looking at just some of the areas where the B-Train is used extensively such as in the transportation of grain, fuel, bulk goods, containers, wood-chips, refrigerated goods and even logs. And the number of dual-purpose ‘platypus’ tanks used for hauling fuel in one direction and a deck load the other seems to be growing daily.

Various Canadian B-Trains

In terms of development, it would appear that there is really very little scope left where the B-Train configuration is concerned. As will be seen from the above, the idea has been adopted by countries as far afield as Sweden in Northern Europe and New Zealand in the South Pacific and by operators hauling anything from asbestos to zinc. So in terms of finding new applications for B-Trains, this seems unlikely. Similarly, the concept is now widely accepted by drivers, many of whom say they prefer hauling a B-train to a single semi trailer because of the feeling of increased stability. Australian designers appear to have taken the idea to its practical limits in terms of size and weights so perhaps the only way the B-Train will develop is in the areas or countries where it has yet to be widely accepted. It is already evident that with the exception of Michigan and Washington states, there appears to be very little take-up of the idea in the U.S.A. so there is enormous potential there. And there are other countries such as Argentina and Chile in South America where the idea could easily find acceptance.

However, it is encouraging to see that development is on-going, albeit the changes reflect refinement of an existing idea rather than radical new concepts. For example, research into the transport of long logs has been carried out by the Forest Engineering Research Institute of Canada (FERIC) using a tri-drive tractor and a special B-Train with a sliding pin mechanism on the second trailer. Such ideas demonstrate the will to further exploit the uses of B-Trains. Dan Keeney. What have you started? Thanks to Mike Beesley, Pete Connock, Ford Motor Company (Australia) Freightliner (Australia) Arthur Ingram, Walt Keeney, Kenworth Trucks (Australia) Keith Robertson and Richard Tew for the use of their illustrations where necessary. Thanks also to Charles Wilson of Modern Bulk Transporter magazine for information on the markets in Brazil and Mexico.

If anyone visiting this site has information which supports or contradicts this information or can help in any way with additional material,
please contact either Hank Suderman or Martin Phippard. Thank you.