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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.
Early tramways and railways were laid out with very gentle grades because locomotive and horse haulage were so low in tractive effort. The only exception would be with a line that was downhill all the way for loaded traffic. Brakes were very primitive at this early stage.
Where a railway has to cross a range of mountains, it is important to lower the summit as much as possible, as this reduces the steepness of the gradients on either side. This can be done with a summit tunnel or a deep summit cutting.
A summit tunnel can lower the summit even more, and steeper hills result in shorter tunnels. Also, tunnels cost the same no matter how much overburden there is, while cuttings tend to increase in cost with the square of the overburden.
Care had to be taken with summit tunnels in the early days of steam with designs that suffered from problems with smoke and slippery rail.
The ruling gradient of a section of railway line between two major stations is the gradient of the steepest stretch. The ruling gradient governs the tonnage of the load that the locomotive can haul reliably.
Some of the techniques that can be used to overcome steep hills include:
A funicular is a type of cable railway system that connects points along a railway track laid on a steep slope. The system is characterized by two counterbalanced carriages permanently attached to opposite ends of a haulage cable, which is looped over a pulley at the upper end of the track. The result of such a configuration is that the two carriages move synchronously: as one ascends, the other descends at an equal speed. This feature distinguishes funiculars from inclined elevators, which have a single car that is hauled uphill.
A mountain railway is a railway that operates in a mountainous region. It may operate through the mountains by following mountain valleys and tunneling beneath mountain passes, or it may climb a mountain to provide transport to and from the summit.
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 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 Broadmoor Manitou and Pikes Peak Cog Railway is a cog railway that climbs one of the most iconic mountains in the United States, Pikes Peak in Colorado. The base station is in Manitou Springs, near Colorado Springs.
The Rimutaka Incline was a 3-mile-long (4.8 km), 3 ft 6 in gauge railway line on an average grade of 1-in-15 using the Fell system between Summit and Cross Creek stations on the Wairarapa side of the original Wairarapa Line in the Wairarapa district of New Zealand. The term "Rimutaka Incline" is sometimes used incorrectly to refer to other parts or all of the closed and deviated section of the Wairarapa Line between Upper Hutt and Speedy's Crossing, near Featherston. The incline formation is now part of the Remutaka Rail Trail.
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.
The Nilgiri Mountain Railway (NMR) is a 1,000 mmmetre gauge railway in Nilgiris district, Tamil Nadu, India, built by the British in 1908. The railway is operated by the Southern Railway and is the only rack railway in India.
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.
A cable railway is a railway that uses a cable, rope or chain to haul trains. It is a specific type of cable transportation.
A bank engine, banking engine, helper engine or pusher engine is a railway locomotive that temporarily assists a train that requires additional power or traction to climb a gradient. Helpers/bankers are most commonly found in mountain divisions, where the ruling grade may demand the use of substantially greater motive power than that required for other grades within the division.
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 South Devon Banks are a series of steep inclines on the ex-GWR railway line linking Exeter and Plymouth in Devon, England. These two cities are separated by the rocky uplands of Dartmoor forcing the early railway surveyors to propose that the line skirt the difficult terrain of the comparatively sparsely populated moorland. Isambard Kingdom Brunel, in surveying the South Devon Railway, opted to push a line along a coastal strip between the Exe and Teign valleys, and then to climb the southern outliers of Dartmoor making for the head of the Plym estuary. From Newton Abbot, the line climbs Dainton Bank, and from Totnes it climbs Rattery Bank, reaches a peak at Wrangaton summit, and then descends Hemerdon Bank to reach Plymouth. These three are collectively known as the South Devon Banks.
The Düsseldorf–Elberfeld railway is a 27 km long main line railway in Germany, originally built by the Düsseldorf-Elberfeld Railway Company, connecting Düsseldorf and Elberfeld via Erkrath, Hochdahl and Vohwinkel. It is served by Regional Express, Regionalbahn and S-Bahn trains.
Erkrath station is a through station in the town of Erkrath in the German state of North Rhine-Westphalia. It has two platform tracks and it is classified by Deutsche Bahn as a category 5 station.
An inclined elevator or inclined lift is a form of cable railway that hauls rail cars up a steep gradient.
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.