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A steep grade railway is a railway that ascends and descends a slope that has a steep grade. Such railways can use a number of different technologies to overcome the steepness of the grade.
Many steep grade railways are located in mountain regions, and are hence also mountain railways. Such railways may form part of infrastructure provided for use by tourists, or as provision for winter sports.
Other steep grade railways are located in hilly urban areas. Again these may be largely tourist oriented, or may be used as part of the local public transport provision.
On steep grades the friction between the wheels and the rails cannot apply sufficient adhesion to the train's wheels so as to overcome gravity, and the train is in danger of sliding down the track. In practice this affects downhill braking capability before it affects uphill climbing ability, and some mountain railways at the lower end of the steepness spectrum rely on standard adhesion for propulsion, but use special track brakes acting directly on the rails.
Where the line is too steep to rely on adhesion for climbing, a rack railway may be used, in which a toothed cog wheel engages with a toothed rack rail laid between the tracks. A now little used alternative to the rack and pinion railway is the Fell system, in which traction and/or braking wheel are applied to a central rail under pressure.
Another alternative is a cable car in which the car runs on rails, but grasps a continuously moving cable underneath the rails for propulsion, releasing the cable to stop. This is used in San Francisco's famous cable cars.
Finally at the steepest end of the spectrum, a funicular railway may be used. Here a cable is used to haul counterbalanced trains up and down the track. The cars are permanently attached to the cable, which stops, starts and reverses as required. Cars are often custom built for the slope, with specially raked seating and steps rather than a sloped floor.
Taken to its logical conclusion as the slope becomes vertical, a funicular becomes an elevator.
A cable car is a type of cable railway used for mass transit in which rail cars are hauled by a continuously moving cable running at a constant speed. Individual cars stop and start by releasing and gripping this cable as required. Cable cars are distinct from funiculars, where the cars are permanently attached to the cable.
A funicular is a transportation system that uses cable-driven cars to connect points along a steep incline. By definition, a funicular uses two counterbalanced passenger cars attached to opposite ends of the same cable, which is looped over a pulley at the upper end of a track.
Cable transport is a broad class of transport modes that have cables. They transport passengers and goods, often in vehicles called cable cars. The cable may be driven or passive, and items may be moved by pulling, sliding, sailing, or by drives within the object being moved on cableways. The use of pulleys and balancing of loads moving up and down are common elements of cable transport. They are often used in mountainous areas where cable haulage can overcome large differences in elevation.
A rack railway is a steep grade railway with a toothed rack rail, usually between the running rails. The trains are fitted with one or more cog wheels or pinions that mesh with this rack rail. This allows the trains to operate on steep grades above 10%, which is the maximum for friction-based rail. Most rack railways are mountain railways, although a few are transit railways or tramways built to overcome a steep gradient in an urban environment.
The Snowdon Mountain Railway is a narrow gauge rack and pinion mountain railway in Gwynedd, north-west Wales. It is a tourist railway that travels for 4.7 miles (7.6 km) from Llanberis to the summit of Snowdon, the highest peak in Wales.
The grade of a physical feature, landform or constructed line refers to the tangent of the angle of that surface to the horizontal. It is a special case of the slope, where zero indicates horizontality. A larger number indicates higher or steeper degree of "tilt". Often slope is calculated as a ratio of "rise" to "run", or as a fraction in which run is the horizontal distance and rise is the vertical distance.
The Fell system was the first third-rail system for railways that were too steep to be worked by adhesion on the two running rails alone. It uses a raised centre rail between the two running rails to provide extra traction and braking, or braking alone. Trains are propelled by wheels or braked by shoes pressed horizontally onto the centre rail, as well as by the normal running wheels. Extra brake shoes are fitted to specially designed or adapted Fell locomotives and brake vans, and for traction the locomotive has an auxiliary engine powering horizontal wheels which clamp onto the third rail. The Fell system was developed in the 1860s and was soon superseded by various types of rack railway for new lines, but some Fell systems remained in use into the 1960s. The Snaefell Mountain Railway still uses the Fell system for (emergency) braking, but not for traction.
The São Paulo Railway Company was a privately owned British railway company in Brazil, which operated the 1,600 mm gauge railway from the seaport at Santos via São Paulo to Jundiaí. The company was nationalised in 1946 and became the Estrada de Ferro Santos-Jundiaí.
Hillclimbing is a problem faced by railway systems when a load must be carried up an incline. While railways have a great ability to haul very heavy loads, this advantage is only significant when the tracks are fairly level. As soon as the gradients increase, the tonnage that can be hauled is greatly diminished.
A gravity railroad or gravity railway is a railroad on a slope that allows cars carrying minerals or passengers to coast down the slope by the force of gravity alone. The speed of the cars is controlled by a braking mechanism on one or more cars on the train. The cars are then hauled back up the slope using animal power, a locomotive or a stationary engine and a cable, a chain or one or more wide, flat iron bands. A much later example in California used 4 ft 8 1⁄2 instandard gauge steam engines to pull gravity cars back to the summit of Mt. Tamalpais.
The Pilatus Railway is a mountain railway in Switzerland and is the steepest rack railway in the world, with a maximum gradient of 48% and an average gradient of 35%. The line runs from Alpnachstad, on Lake Alpnach, to a terminus near the Esel summit of Pilatus at an elevation of 2,073 m (6,801 ft), which makes it the highest railway in the canton of Obwalden and the second highest in Central Switzerland after the Furka line. At Alpnachstad, the Pilatus Railway connects with steamers on Lake Lucerne and with trains on the Brünigbahn line of Zentralbahn.
The Montserrat Rack Railway is a mountain railway line north-west of Barcelona in Catalonia, Spain. The line runs from Monistrol de Montserrat to the mountain-top monastery of Montserrat.
A cable railway is a railway that uses a cable, rope or chain to haul trains. It is a specific type of cable transportation.
The term ruling grade is usually used as a synonym for "steepest climb" between two points on a railroad. More simply, the steepest grade to be climbed dictates how powerful the motive power must be in order for the run to be made without assistance. Even if 99% of the line could be run with a low-powered locomotive, if at some point on the line there is a steeper gradient than such train would be able to climb, this gradient "rules" that a more powerful locomotive must be used, in spite of it being far too powerful for the rest of the line. This is why special "helper engines" are often stationed near steep grades on otherwise mild tracks. It is cheaper than running a too-powerful locomotive over the entire track mileage just in order to make the grade, especially when multiple trains run over the line each day.
Line C of the Lyon Metro is the modern incarnation of the Funiculaire Croix-Rousse - Croix-Paquet, an old cable-hauled railway operating on part of the current alignment.
The Lynton and Lynmouth Cliff Railway is a water-powered funicular railway joining the twin towns of Lynton and Lynmouth on the rugged coast of North Devon in southwest England.
Track brakes are a form of brakes unique to railborne vehicles. The braking force derives from the friction resulting from the application of wood or metal braking shoes directly to the tracks. Early examples of track brakes used on the horse hauled mineral tramways that preceded the steam locomotive were described as sledge brakes, and are usually associated with lines that used gravity propulsion. In 1849 locomotive engineer Daniel Gooch fitted early examples of his Corsair Class tank engine with these devices; later these were replace with a conventional wheel brake.
A wheelset is the wheel–axle assembly of a railroad car. The frame assembly beneath each end of a car, railcar or locomotive that holds the wheelsets is called the bogie. Most North American freight cars have two bogies with two or three wheelsets, depending on the type of car; short freight cars generally have no bogies but instead have two wheelsets.
The American Fork Railroad was a 16 miles (30 km) long narrow gauge railway with a gauge of 3 ft from American Fork to Forest City in Utah, which operated from 1872 to 1878.
