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 Mason Bogie Single Fairlie, 1874 | |||||||||||||||||
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Under the Whyte notation for the classification of steam locomotives, 0-6-6 represents the wheel arrangement of no leading wheels, six powered and coupled driving wheels on three axles and six trailing wheels on three axles. All locomotives with this wheel arrangement were tank locomotives; no 0-6-6 tender locomotives were recorded.
The 0-6-6 wheel arrangement was usually found on Single Fairlie or Mason Bogie locomotives. The Fairlie locomotive was invented and patented in 1864 by the Scottish engineer Robert Francis Fairlie. The first Fairlie locomotives later became known as Double Fairlies. [1] [2]
A variation of the original Fairlie concept was the Single Fairlie, also known as the Mason Fairlie. The Single Fairlie design was essentially half a Double Fairlie. It retained the ability to negotiate sharp curves and, while it abandoned the bidirectional nature of the Double Fairlie, it regained the ability of conventional locomotives to have a large water and coal bunker behind the cab and to use a trailing tender if necessary. [1] [2]
Most Single Fairlies were tank locomotives and early models were similar in general appearance to conventional tank engines with side tanks and a coal bunker aft of the cab, all mounted on a single rigid frame. The pivoting engine unit was mounted under the boiler and the unpowered bogie under the cab and bunker. [1] [2]
Later models were similar in appearance to conventional tender locomotives. It was developed by William Mason in the United States, where the type became known as the Mason Bogie. It had one boiler at the front, a cab in the centre and a water-and-coal bunker at the rear end, all mounted on a single rigid frame, with a single engine unit under the boiler and an unpowered bogie under the bunker. [1] [2] [3]
The first known 0-6-6T locomotive was built for the 3 ft (914 mm) gauge New Bedford Railroad by Mason Machine Works in May 1874. It was apparently not numbered, but bore the name Wm. Mason. The locomotive later went to the Boston, Clinton & Fitchburg as its no. 23, then to the Old Colony as its no. 108 and finally to the New York, New Haven & Hartford as its no. 708. [3]
More 0-6-6T locomotives were produced by Mason between 1875 and 1881. Many of them were subsequently rebuilt to a 2-6-6T wheel arrangement. [3]
Mason Bogie locomotives are a type of articulated tank locomotive suited for sharp curves and uneven track, once commonly used on narrow-gauge railways in the United States. The design is a development of the Single Fairlie locomotive.
A Fairlie is a type of articulated steam locomotive that has the driving wheels on bogies. The locomotive may be double-ended or single ended. Fairlies are most famously associated with the Ffestiniog Railway in North Wales.
A tank locomotive or tank engine is a steam locomotive that carries its water in one or more on-board water tanks, instead of a more traditional tender. Most tank engines also have bunkers to hold fuel; in a tender-tank locomotive a tender holds some or all of the fuel, and may hold some water also.
An articulated locomotive is a steam locomotive with one or more engine units that can move independent of the main frame. Articulation allows the operation of locomotives that would otherwise be too large to negotiate a railroad's curves, whether mainlines or special lines with extreme curvature such as logging, industrial, or mountain railways.
On a steam locomotive, a trailing wheel or trailing axle is generally an unpowered wheel or axle (wheelset) located behind the driving wheels. The axle of the trailing wheels is usually located in a trailing truck. On some large locomotives, a booster engine was mounted on the trailing truck to provide extra tractive effort when starting a heavy train and at low speeds on gradients.
Under the Whyte notation for the classification of steam locomotives by wheel arrangement, a 4-6-2+2-6-4 is a Garratt or Union Garratt articulated locomotive using a pair of 4-6-2 engine units back to back, with the boiler and cab suspended between them. The 4-6-2 wheel arrangement of each engine unit has four leading wheels on two axles, usually in a leading bogie, six powered and coupled driving wheels on three axles, and two trailing wheels on one axle, usually in a trailing truck. Since the 4-6-2 type is known as a Pacific, the corresponding Garratt type is usually known as a Double Pacific.
The Forney is a type of tank locomotive patented by Matthias N. Forney between 1861 and 1864 and used predominantly in the USA.
Under the Whyte notation for the classification of steam locomotives by wheel arrangement, a 4-8-2+2-8-4 is a Garratt articulated locomotive consisting of a pair of 4-8-2 engine units back to back, with the boiler and cab suspended between them. The 4-8-2 wheel arrangement has four leading wheels on two axles, usually in a leading bogie, eight powered and coupled driving wheels on four axles and two trailing wheels on one axle, usually in a trailing truck. Since the 4-8-2 type is generally known as a Mountain, the corresponding Garratt type is usually known as a Double Mountain.
Under the Whyte notation for the classification of steam locomotives by wheel arrangement, 2-6-2+2-6-2 is an articulated locomotive using a pair of 2-6-2 power units back to back, with the boiler and cab suspended between them. The 2-6-2 wheel arrangement has a single pair of leading wheels in a leading truck, followed by three coupled pairs of driving wheels and a pair of trailing wheels in a trailing truck. Since the 2-6-2 type was often called the Prairie type, the corresponding Garratt and Modified Fairlie types were usually known as a Double Prairie.
Under the Whyte notation for the classification of steam locomotives by wheel arrangement, a 2-8-2+2-8-2 is an articulated locomotive using a pair of 2-8-2 power units back to back, with the boiler and cab suspended between them. The 2-8-2 wheel arrangement has a single pair of leading wheels in a leading truck, followed by four coupled pairs of driving wheels and a pair of trailing wheels in a trailing truck. Since the 2-8-2 type was known as Mikado, the corresponding Garratt and Modified Fairlie types were usually known as Double Mikado.
Córas Iompair Éireann No. CC1, generally known as the Turf Burner, was a prototype 0-6-6-0 articulated steam locomotive designed by Oliver Bulleid to burn turf and built at CIÉ's Inchicore Works in Dublin. CC1 shared some, but not all, of the characteristics of Bulleid's previous attempt to develop a modern steam locomotive, the Leader. Like the one completed Leader, CC1 had a relatively short career and was never used in front-line service. It was the last steam locomotive to be constructed for an Irish railway.
The South African Railways Class 21 2-10-4 of 1937 was a class of steam locomotives used in South Africa.
The South African Railways Class FC 2-6-2+2-6-2 of 1925 was an articulated steam locomotive.
The South African Railways Class GEA 4-8-2+2-8-4 of 1946 was an articulated steam locomotive.
The South African Railways Class GM 4-8-2+2-8-4 of 1938 was an articulated steam locomotive.
The Cape Government Railways Fairlie 0-6-0+0-6-0 of 1876 was a South African steam locomotive from the pre-Union era in the Cape of Good Hope.
The Cape Government Railways 4th Class 4-6-0TT of 1884 was a South African steam locomotive from the pre-Union era in the Cape of Good Hope.
The South African type FT tender was a steam locomotive tender.
The South African type JV tender was a steam locomotive tender.
Rigid-framed electric locomotives were some of the first generations of electric locomotive design. When these began the traction motors of these early locomotives, particularly with AC motors, were too large and heavy to be mounted directly to the axles and so were carried on the frame. One of the initial simplest wheel arrangements for a mainline electric locomotive, from around 1900, was the 1′C1′ arrangement, in UIC classification.
