About Wire Rope News & Sling Technology
Contact Wire Rope News
Read the Current Issue Online!
Wire Rope News home page Search our Database for the Product You Need News in Our Industry Subscribe to Wire Rope News Classified Ads Links of Interest
NEWS > NOV 2019

Table Mountain Aerial Cableway

Table Mountain is a flat-topped sandstone mountain that juts from the Cape Peninsula of South Africa.

South Africa’s capital, Cape Town, grew up in the mountain’s shadow. Residents and visitors always looked up. Opened on October 4, 1929, the Table Mountain Aerial Cableway was built by Adolf Bleichert & Co. and has carried over 28 million people to the mountain’s summit in its 90 years of operation.

Table Mountain
A Rotair cabin approaches the Upper Station. Lion’s Peak, Cape Town, and Roben Island are in the background (photo: F. Williams)

by Peter von Bleichert

Cape Town was founded in 1652 and is South Africa’s oldest city. Up against the Cape Fold Range, and nestled between the South Atlantic and Table Mountain’s shoulder, Cape Town was settled by the Dutch East India Company as a way-station for ships traveling around the Cape of Good Hope and on to the Dutch East Indies.

Cape Town is located in one of Earth’s six floral kingdoms, the Cape Floristic Region, home to endemic fauna and flora. Recognized as a UNESCO World Heritage Site and one of the New Wonders of Nature, the Cape Floristic Region includes Table Mountain National Park, as well as seven other protected areas around Cape Town. Since Cape Town’s founding, Table Mountain and its unique environment have enticed the adventurous to climb and explore.

Table Mountain could only be climbed by foot in the 1870s. A funicular was proposed and approved, but the First Anglo-Boer War interrupted plans in 1880. In 1912 it was decided that a rack railway would be constructed. However, the outbreak of World War I in 1914 meant this project got sidelined as well.

The question of how best to scale Table Mountain came up again in 1926, and Norwegian engineer Trygve Stromsoe proposed to the Cape Town City Council an aerial wire ropeway, a cableway. Despite high cost, some £60,000 of the day (~15 million 2019 USD), the citizens of Cape Town voted in favor of a cableway. The Table Mountain Aerial Cableway Company (TMACC) was formed to finance the project.

The TMACC board comprised businesspersons Sir Alfred Hennessy, Sir David Graaff, Sir Ernest Oppenheimer, as well as the engineer, Stromsoe.

On November 16, 1926, TMACC contracted with Adolf Bleichert & Co. to build the Table Mountain Aerial Cableway. Bleichert’s engineers and production halls got to work.

DESIGN

By its 50th Anniversary in 1924, Adolf Bleichert & Co. had constructed 3,000 miles of wire ropeway systems around the world. Bleichert’s headquarters and primary factory were located in Leipzig, Germany, and the company was preeminent in the materials transport market. Seeking to diversify and grow, a dedicated passenger division was formed in 1924 called Adolf Bleichert & Co. Drahtseilbahnbau GmbH.

Bleichert’s passenger division went on to build many iconic passenger systems including the Zugspitzbahn (WRN, Oct. 2009), the Port Vell Aerial Tramway, the Aeri de Montserrat, and, the oldest original operating passenger wire ropeway in the world, the Predigtstuhlbahn (WRN, Oct. 2018). Related to its formation, Bleichert’s passenger division had also entered into an alliance with Italian engineer-industrialist Luis Zuegg.

The resultant Bleichert-Zuegg System permitted sweeping rope spans between support towers, as well as increased cabin weights and speed of travel. The basic Bleichert-Zuegg System comprised two passenger cabins supported by a looped track rope and secured to each other by a looped hauling rope. The system counterbalanced the cabins, with one at the lower station when the other was at the upper station. The weight of a descending cabin maximized ascension energy for its counterpart and eased the burden on the ropeway’s drive motor. The system included an auxiliary hauling rope that could take over from the primary hauling rope when needed, though otherwise remained parked.

For Table Mountain Aerial Cableway, Bleichert delivered two of its ‘Rectangular’ cabins to travel between a Lower Station and an Upper Station. Made of corrugated iron sheet panels and iron frame and hanger, the cabins had a maximum capacity of 24 passengers and 1 conductor each. With a line speed of 11.2 miles per hour, the cabins moved at 16.4 feet per second, and could climb Table Mountain in under 5 minutes. Communication with the control room is by telephone signal transmitted via the hauling rope. There is a 3,960 foot/0.75-mile rope span between stations with no support towers. Bleichert delivered its spiral track and locked hauling wire ropes which weighed some 18 tons combined.

STATIONS

Local architects Walgate & Ellsworth under specifications outlined by Bleichert designed the Lower and Upper Stations. Construction of the station buildings was subcontracted to local industry, with Bleichert manufacturing all system components at its German factories, and shipping them to South Africa. In order to move materials and workforce, Bleichert installed a temporary ropeway at the Lower Station worksite and up to Africa Ledge, location of the Upper Station. When the buildings were done, Bleichert’s technicians installed and tested all the cableway’s equipment. Generally, both stations housed cableway components, electricity generators, cabin platforms, and other customer and engineering support facilities.

The Lower Station is at 1,190 feet above sea level. It is located on Tafelberg (Table Mountain) Road inside Table Mountain National Park in the Garden neighborhood of Cape Town, some 15-minutes from the city’s downtown and waterfront. The Lower Station houses dual cabin platforms, sheave wheels, and two 149-ton rope-tensioning counterweights slung in 40-foot-deep shafts. The building also has administrative and facility spaces, as well as a visitor center and a shop.

A cabin emerges from the Lower Station. It begins a steep climb that matches that of the mountain’s sloped granite skirt. The ropes run parallel to India Ravine and fly over India Venster trail up to where it meets Table Mountain Lower Station trail. Table Mountain then rears suddenly and its geology changes from granite to a near vertical sandstone plateau. The cabin ascends the wall of the Western Table, gliding high above a bowl formed between Africa Ledge and Kloof Corner Ridge. The cabin gets slammed by a strong gust off the Atlantic Ocean.

The cabin sways and creaks, and the vibrating wire rope bounces. Passengers laugh nervously. Ahead, Upper Station stands on the precipice of Africa Ledge. The cabin approaches the station’s arched mouth and slows to meet the platform.

The Upper Station sits at 3,500 feet above sea level, some 2,310 feet higher than the Lower Station. A veneer of native stone blends the building into the surrounding geology. Upper Station houses the electric primary and auxiliary rope drives, transmissions, sheave wheels, a control room, docking rails, and a single movable cabin platform that can access either track rope. The control room provided a clear view down the line, had a back-up handbraking system, line throttle, indicator panels, signal bells, a telephone system for communicating with the Lower Station and cabins, as well as access to the machine and rope spaces. The cabin parks and passengers disembark, exiting Upper Station on to a sweeping paved patio. There is a mailbox that offers a unique Table Mountain postmark, and trailheads that promise ways to the Table Mountain Café, memorials, and observation points around the Western, Central, and Eastern Table. Standing at the station, the view includes Lion’s Head Peak, Cape Town, Table Bay, and Robben Island, as well as the flat expanse of the Table with Devil’s Peak and the Atlantic seaboard to the south and west. Visitor amenities include audio or guided walking tours, the Table Mountain Café, a wi-fi lounge, historical registered structure, and various observation points.

After two years of challenging construction, on October 4, 1929, Cape Town’s Mayor Rev. A.J.S. Lewis opened the Table Mountain Aerial Cableway to its citizens and the world.

Table Mountain
An early 1930s passenger leans out of the rectangular cabin of the Table Mountain Aerial Cableway to take in the grand view before reaching the summit.

TMAC UPDATES

The Table Mountain Aerial Cableway has been updated four times since opening day: in 1958, 1967, 1974, and, most extensively, in 1997.

The 1958 update replaced the original Bleichert 25-passenger cabins with new all-metal ones that held 27 passengers. The original wire ropes made by Bleichert were changed out, too, with new ones made in South Africa. The 1958 cabins ran until 1966. The 1967 update included new cabins that held 28 passengers, and the electric drive motors and transmission were replaced in the Upper Station. Further, the ropes were lowered to the ground and electro-magnetically inspected.

The 1974 update replaced the 1967 cabins with newer, lighter ones, though cabin capacity remained the same at 28 passengers. The most ambitious and expensive update occurred in 1997. Under new ownership and contending with six-hour wait times at the busy cableway, the TMACC embarked on extensive modernization of the system. An R87 million (about 10 million 2019 US dollars) contract was signed with ropeway engineering firm Garaventa AG of Switzerland for installation of a Rotair-car System at Table Mountain. Table Mountain Aerial Cableway’s rope layout was changed from the original Bleichert bi-rope to Garaventa’s modern tri-rope type. The tri-rope consisted of dual full-locked coil 238-ton rated track ropes and 75-ton rated haul and heel ropes. The new system located each cabin at the opposite end of the haul and heel ropes for counterbalance, operating in a jig-back system that harkens to Bleichert-Zuegg. The system’s dual track ropes could carry heavier loads while providing lateral separation that countered cabin sway in windy conditions. Primary control of the line was changed from the Upper to the Lower Station, and new rope anchors were installed consisting of 9-foot concrete bollards with 45-foot long steel anchors driven into the rockface. With a new tensioning system, counterweights were reduced to 134 tons. Lastly, the 1997 update included new cabins.

ROTAIRS

‘Rotair’ cabins were purchased from Swiss manufacturer CWA, now a subsidiary of the Doppelmayr-Garaventa Group. Rotair cabins were known for their use at Mt. Titlis, Engelberg, Switzerland, and, Mt. San Jacinto, Palm Springs, USA. The cabins utilize aircraft grade materials and are round, making them less susceptible to winds. The cabins can take on 793 gallons of fresh water in a tank beneath their floor. The water acts as ballast against high winds, expanding the cableway’s operating envelope to 37 mph gusts, and can be transferred to a reservoir at the Upper Station for use at the restaurant and other mountaintop facilities. A Rotair cabin holds 64 passengers plus one cabin master, or, alternatively, the cabin can haul 5 tons of payload up the mountain, supplying the restaurant, shops, and café. Rotairs are named for their rotating floor that provides passengers with panoramic views. A waste tank can be slung beneath the cabin to bring sewage down to the Lower Station for dumping into Cape Town’s municipal system.

Each cabin and its hanging gear weigh approximately 11 tons, and is suspended from the track ropes with a 24-wheel carriage and hanger. This running gear sports special shafts equipped with dampers that ensure optimal contact between the wheels and rope, further reducing cabin swing.

POWER & BRAKES

A 540kW alternating current induction motor was installed in 2013, and is controlled by four variable frequency drives. If municipal electricity is cut, the cable has two back-up hydraulic systems that can power the cableway. The first is powered by a Volvo engine and the second with one from Deutz.

Braking the line is accomplished with the service brake that affects the gearbox shaft of the haul rope, and there is an emergency brake that can stop the haul rope drive wheel. Lastly, a cabin master can brake and lock a cabin independent of station control. The new Rotair-car System allowed a line speed of 33 feet per second, some 19 feet faster than before. The new capacity and speed provided by the 1997 update enabled Table Mountain Aerial Cableway to carry 800 passengers per hour in trips of under five-minutes between stations.

Both stations were modified in 1997 to accommodate new machinery, the larger cabins, and were generally refurbished. Cabins from 1958 and 1974 were converted to information and ticket booths and were installed near the Lower Station entrance.

The cableway was closed in 1996 for construction, then reopened on October 4, 1997, the 68th Anniversary of the cableway’s opening day in 1929. Ridership soared with the improvements. In the high season, upwards of 10,000 people ride the cableway per day, and 2018 saw record overall ridership of 855,000.

The Table Mountain Aerial Cableway is one of Africa’s greatest tourist attractions, and celebrates its 90th Anniversary on October 4, 2019. Party plans include a stakeholder event on October 4th, and a variety of entertainment the weekend of October 4-6 at the Lower Station. Further, locals will enjoy promotion pricing the whole month of October, and there are plans for monthly activities at the stations until September 2020. Of course, the all-important staff will be celebrated, too. The Table Mountain Aerial Cableway has a rich engineering history, and continues its endless journey at Cape Town’s Table Mountain.

The author is the great-great grandson of Adolf Bleichert.

 

Wire Rope industry Supplier Directory

Click Online Suppliers Directory and search some of the TOP wire rope providers in the industry!

< more Wire Rope & Sling Technology News

 

Caldwell Lifting Solutions
Suncor Stainless
The Crosby Group
Yoke Industrial Corp.
Strider~Resource
Wirop Americas
SlingMax Rigging Solutions
Campbell Chain & Fittings
Chant Engineering
Ken Forging - industrial hardware
Maskell Rigging
Loos wire rope, cable and fittings products
Associated Wire Rope & Rigging
All Material Handling
Landmann Wire Rope Products
Tandemloc

Be sure to visit our
advertisers by clicking on
the above banners!
Wire Rope News Home Page