A trailer bus or articulated trailer bus is a bus

Bus

A bus is a road vehicle designed to carry passengers. Buses can have a capacity as high as 300 passengers. The most common type of bus is the single-decker bus, with larger loads carried by double-decker buses and articulated buses, and smaller loads carried by midibuses and minibuses; coaches are...

 formed out of a bus bodied semi-trailer

Semi-trailer

A semi-trailer is a trailer without a front axle. A large proportion of its weight is supported by a road tractor, a detachable front axle assembly known as a dolly, or the tail of another trailer...

 pulled by a conventional tractor unit

Tractor unit

A tractor unit, prime mover , road tractor, or traction unit is a heavy-duty commercial vehicle within the large goods vehicle category, usually with a large displacement diesel engine, and several axles. The tractor unit serves as a method of moving trailers...

 in the same way as a conventional articulated

Articulated vehicle

An articulated vehicle is a vehicle which has a permanent or semi-permanent pivoting joint in its construction, allowing the vehicle to turn more sharply. There are many kinds of articulated vehicles, from heavy equipment to buses, trams and trains...

 semi-trailer truck

Semi-trailer truck

A semi-trailer truck, also known as a semi, tractor-trailer, or articulated truck or articulated lorry, is an articulated vehicle consisting of a towing engine , and a semi-trailer A semi-trailer truck, also known as a semi, tractor-trailer, or (in the United Kingdom and Ireland) articulated truck...

.

Trailer buses are usually pulled by a conventional truck from various truck manufacturers, while others have larger space cabs

Cabin (truck)

The cab of a truck is an enclosed space in a truck where the driver is seated. The word originated as a short form of cabriolet, not cabin. Some may refer to the tractor unit of a semi-trailer truck as a cab, but this is not the subject of this article...

. Trailer bus bodies are built by various local builders.

History

An early trailer bus was designed in Amsterdam

Amsterdam

Amsterdam is the largest city and the capital of the Netherlands. The current position of Amsterdam as capital city of the Kingdom of the Netherlands is governed by the constitution of August 24, 1815 and its successors. Amsterdam has a population of 783,364 within city limits, an urban population...

 in the 1920s as bus designs got longer. As a solution to possible grounding hazards on humped bridges, three prototypes were built in 1924, but proved to be problematic, and later converted to rigid bodies in 1927.

During World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

 and in the immediate post-war years, trailer buses were turned to as a simple and economical way of providing bus transport to replace worn out conventional bus fleets. The semi-trailers were basic and uncomfortable, but each could carry more passengers than an ordinary single-decker bus, and nearly as many as a double-decker bus

Double-decker bus

A double-decker bus is a bus that has two storeys or 'decks'. Global usage of this type of bus is more common in outer touring than in its intra-urban transportion role. Double-decker buses are also commonly found in certain parts of Europe, Asia, and former British colonies and protectorates...

. Indeed at least one double-decker trailer bus was known to have been built for service in India

India

India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...

.

In Australia

Australia

Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

, 123 semi-trailer type buses were built between 1939 and 1984; one example, a 1947 semi-trailer coupled with an American-built 1943 White

White Motor Company

White Motor Company was an American automobile and truck manufacturer from 1900 until 1980. The company also produced bicycles, roller skates, automatic lathes, and sewing machines. Before World War II, the company was based in Cleveland, Ohio.-History:...

 M3A1 tractor, is now located in Sydney Bus Museum

Sydney Bus Museum

Sydney Bus Museum is a not-for-profit transportation museum and education centre for public benefit located in the suburb of Leichhardt, in Sydney, Australia....

 in Sydney, New South Wales. The Sydney exhibit was the last trailer bus used in NSW, withdrawn in 1977.

Trailer buses were also used in Perth, Western Australia

Perth, Western Australia

Perth is the capital and largest city of the Australian state of Western Australia and the fourth most populous city in Australia. The Perth metropolitan area has an estimated population of almost 1,700,000....

, from 1952 onwards, purchased by Western Australian Government Railways

Western Australian Government Railways

Western Australian Government Railways was most common name of the Western Australian government rail transport authority from 1890 to 1976. It is, in its current form, known as the Public Transport Authority of Western Australia....

, with the trailer bodies built by Scarborough Bus Services.

In 1948, ten British-built trailer buses saw service as a staff canteens for London Transport

London Transport Executive

The London Transport Executive was the organisation responsible for public transport in the Greater London area, UK, between 1948-1962. In common with all London transport authorities from 1933 to 2000, the public name and operational brand of the organisation was London Transport.-Creation:On 1...

 (in country green livery) with one passing to the Cobham Bus Museum in 1972.

A large order for 1175 buses from the Netherlands

Netherlands

The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...

 Railways for buses from Crossley

Crossley Motors

Crossley Motors was a British motor vehicle manufacturer based in Manchester, England. They produced approximately 19,000 high quality cars from 1904 until 1938, 5,500 buses from 1926 until 1958 and 21,000 goods and military vehicles from 1914 to 1945.Crossley Brothers, originally...

 included an order for 250 trailer buses, each to carry 52 seated and 28 standing passengers. The tractor units were delivered as short Crossley DD42s, and these were matched in Holland with DAF

DAF Trucks

DAF Trucks NV is a Dutch truck manufacturing company and a division of PACCAR. Its headquarters and main plant are in Eindhoven. Cabs and axle assemblies are produced at its Westerlo plant in Belgium...

 built trailer chassis fitted with bus bodies.

In the late 1980s, a Mexican-built trailer bus was in test service in the Los Angeles

Los Ángeles

Los Ángeles is the capital of the province of Biobío, in the commune of the same name, in Region VIII , in the center-south of Chile. It is located between the Laja and Biobío rivers. The population is 123,445 inhabitants...

 / Orange County

Orange County, California

Orange County is a county in the U.S. state of California. Its county seat is Santa Ana. As of the 2010 census, its population was 3,010,232, up from 2,846,293 at the 2000 census, making it the third most populous county in California, behind Los Angeles County and San Diego County...

 area of California.

Obsolescence

As early as the mid-1940s, trailer buses began to quickly fall out of favour for a variety of factors:

• The length of trailer buses make them difficult to negotiate sharp turns at narrow street corners;
• Each trailer bus normally requires a two-person crew, with the driver in the tractor and the conductor
  Conductor (transportation)
  A conductor is a member of a railway train's crew that is responsible for operational and safety duties that do not involve the actual operation of the train. The title of conductor is most associated with railway operations in North America, but the role of conductor is common to railways...
  
   in the semi-trailer;
• The perceived danger of a passenger-laden semi-trailer dislodging from its tractor while under way has led to many jurisdictions in the United States, Canada and Australia prohibiting passengers being carried in towed trailers.

Trailer buses saw service until at least 1984 in South Africa

South Africa

The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...

, possibly due to the rugged terrain in its remote areas, and the availability of specialist bus builders as opposed to truck dealers and basic body builders.

Trailer buses are still in service in Cuba

Cuba

The Republic of Cuba is an island nation in the Caribbean. The nation of Cuba consists of the main island of Cuba, the Isla de la Juventud, and several archipelagos. Havana is the largest city in Cuba and the country's capital. Santiago de Cuba is the second largest city...

, where they were introduced under the nickname of "camellos" ("camels", from the twin-humped shape of the trailers) during the so-called "Special Period

Special Period

The Special Period in Time of Peace in Cuba was an extended period of economic crisis that began in 1991 after the dissolution of the Soviet Union and, by extension, the Comecon. The economic depression of the Special Period was at its most severe in the early-to-mid 1990s before slightly declining...

" after the fall of the Soviet Union

Soviet Union

The Soviet Union , officially the Union of Soviet Socialist Republics , was a constitutionally socialist state that existed in Eurasia between 1922 and 1991....

. , the trailer buses are reportedly being gradually retired from service in Havana

Havana

Havana is the capital city, province, major port, and leading commercial centre of Cuba. The city proper has a population of 2.1 million inhabitants, and it spans a total of — making it the largest city in the Caribbean region, and the most populous...

city, replaced by Chinese-made buses.

External links

• Fotopic image, an illustration of the Crossley Dutch trailer bus "LIJNBUS 1947 trailer type Crossley DAF, NZHVM
• Images of trailer buses in South Africa
• Images of trailer buses in South Africa