Railway turntable

A small turntable at the Orange Empire Railway Museum in Perris, CA. This type of turntable with the central tower and supporting cables is called a “gallows turntable”.

A larger turntable in front of a roundhouse, 1909

A small turntable at the Textilmuseum Bocholt

Wagon turntable at the National Slate Museum on 24 gauge track

File:600 Gordon on turntable.jpg

Preserved Longmoor Military Railway engine being turned on a vacuum operated turntable at SVR Kidderminster – note the hose

Drivers turning cable car on a turntable at San Francisco

The right Portal of the building leads to a covered turntable for (rotary) snow ploughs of the Rhätische Bahn on the Bernina Hospiz

In rail terminology, a turntable is a device used to turn railroad rolling stock. When steam locomotives were still in wide use, many railroads needed a way to turn the locomotives around for return trips as their controls were often not configured for extended periods of running in reverse and in many locomotives the top speed was lower in reverse motion. Turntables were also used to turn observation cars so that their windowed lounge ends faced toward the rear of the train.

Overview

The turntable bridge (the part of the turntable that included the tracks and that swiveled to turn the equipment) could span anywhere from 6 to 120 feet, depending on the railroad's needs. Larger turntables were installed in the locomotive maintenance facilities for longer locomotives, while short line and narrow gauge railroads typically used smaller turntables as their equipment was smaller. Turntables as small as 6 feet in diameter have been installed in some industrial facilities where the equipment is small enough to be pushed one at a time by human or horse power.

Roundhouse

In engine maintenance facilities, a turntable was usually surrounded, in part or in whole, by a roundhouse. It was more common for the roundhouse to only cover a portion of the land around a turntable but fully circular roundhouses exist, such as these preserved roundhouses:

• the roundhouse that serves as the basis for the Baltimore and Ohio Railroad Museum in Baltimore, MD
• The Roundhouse in London, England, now an arts centre.

Turntables in North America

Turntables still in use are more common in North America than in Europe, where locomotive design favors configurations with a controller cabin on both ends or in the middle.

Turntables in Great Britain

Vacuum operation

In Britain, where steam hauled trains generally have vacuum operated brakes, it was quite common for turntables to be operated by vacuum motors worked from the locomotive's vacuum ejector or pump via a flexible hose or pipe although a few manually and electrically operated examples exist.

Surviving turntables

Several working examples remain; many on Heritage railways in Great Britain. Examples include: -

• Aberdeen
• Aviemore
• Barrow Hill
• Carnforth
• Churston
• Didcot
• Fort William
• Hornsey
• Kidderminster
• Keighley
• Neville Hill
• NRM York
• Old Oak Common
• Minehead (West Somerset Railway)
• Pickering
• Scarborough
• St Blazey
• Swanage
• Tyseley
• Wansford
• Yeovil Junction

Accidents

In deciding liability for turntable accidents, most state courts followed the precedent set by the United States Supreme Court in Sioux City & Pacific R.R. v. Stout (1873). In that case, a six-year-old child was playing on the unguarded, unfenced turntable when his friends began turning it. While attempting to get off, his foot became stuck and was crushed. The Court held that although the railroad was not bound by the same duty of care to strangers as it was to its passengers, it would be liable for negligence "if from the evidence given it might justly be inferred by the jury that the defendant, in the construction, location, management, or condition of its machine has omitted that care and attention to prevent the occurrence of accidents which prudent and careful men ordinarily bestowf."

In the case of Chicago B. & Q.R. Co. v. Krayenbuhl (1902), a four year old child was playing on an unlocked, unguarded railroad turntable. Other children set the turntable in motion, and it severed the ankle of the young child. The child's family sued the railroad company on a theory of negligence and won at trial. The Nebraska Supreme Court held that the Railroad company may have been liable for negligence after considering the "character and location of the premises, the purpose for which they are used, the probability of injury therefrom, the precautions necessary to prevent such injury, and the relations such precautions bear to the beneficial use of the premises." However, the Supreme Court reversed the trial court's decision based on an improper jury instruction as to the evidence.

Accidents to locomotives sometimes occurred. For example, if a locomotive failed to stop (when the turntable was incorrectly set) it might fall into the turntable pit.

Unusual turntables

• In one location in France, lack of space forced the installation of an asymmetric turntable, where the pivot point was about one-third along its length. Such a turntable cannot rotate 360 degrees.
• At Ventnor railway station, due to lack of space a small turntable was provided to allow steam engines to run around their trains. Similarly Bembridge railway station.
• In Solingen at line 683 there is a turntable for trolleybus. [1]

Multiple turntables

Stations housing large numbers of engines may have more than one turntable:

• – Old Oak Common near Paddington – 4
• Enfield – 2
• Broadmeadow – 2
• Linwood – Formerly 2 (second removed during 1980/1990's)

See also

• Wye – a way of turning whole trains.
• Transfer table (UK: 'traverser') – provides access to two or more parallel tracks in a space saving manner like a turntable, but without the ability to turn.
• At one station on the Rigi-Bahnen in Switzerland, a traverser plate is used in stead of a turnout.

External links

Media related to Rail transport turntables at Wikimedia Commons