The Airport Express route map.
The Chek Lap Kok railway station under construction.
The Rambler Channel Bridge has two central tracks with single tracks on each side.
The Airport Express train running between Chep Lap Kok Airport and Hong Kong.
The train's interior.
Installation of the floating slab track.
Translucent noise barriers – an innovative development.
The spectacular Tsing Ma Bridge is an Anglo-Japanese construction project.
An Airport Express train running across the steel box trackform at Tsing Ma Bridge.

Massive growth in Hong Kong’s importance as a trade and business centre has brought many problems for the island’s existing infrastructure. This, in turn, has slowed down the rate of potential growth at a time when the territory was keen to exploit its position as a force on the world trading scene.

It was therefore considered vital that the territory had modern transport facilities, and the centrepiece of the development of these has been the new Chek Lap Kok International Airport.

THE PROJECT

The new 34km airport railway opened in July 1998 and is used by two distinct services. The Airport Express line offers a fast passenger link between Chek Lap Kok and central Hong Kong. Journeys take 23 minutes with intermediate stops at Kowloon and Tsing Yi, and are served by seven-car trains, offering an all-seated, business class-type service.

The Lantau line offers a more rapid transit service, linking Lantau, West Kowloon and Hong Kong Central. The line serves six stations: Hong Kong, Kowloon, Tai Kok Tsui, Lai King, Tsing Yi and Tung Chung. An interchange with the MTR (mass transit railway) is provided at Lai King. The introduction of this service has brought two major benefits to the territory: traffic on the busy Nathan Road corridor of the MTR has been eased, while journey times between Lai King and Hong Kong Central have been slashed from 23 minutes to just over eight minutes.

INFRASTRUCTURE

Hong Kong has five different rail systems: the heavily-used MTR network, the busy suburban Kowloon Canton railway, the modern light transit (LRT) system, a traditional street tramway and the funicular railway. Each operates independently, but there is considerable interchange between them.

Standard gauge lines for the airport railway are electrified at 1.5kV dc overhead, which gives total compatability with the MTR system. Train speed, at a maximum of 135km/h (80mph), is considerably better than the 80km/h (50mph) which is the norm on MTR.

There are five intermediate stations on the two lines, some of which have separate, segregated platforms for Airport Express and Lantau line services. 8km of the new line is through tunnels, including an immersed tube under Victoria Harbour, and a total of 6km is carried on elevated sections. This includes the spectacular Tsing Ma Bridge, one of the territory’s biggest engineering projects of recent years. One of the world’s longest suspension bridges, it has a central span of 1,377m, one of the longest single spans of any bridge in the world.

With much of the line built on reclaimed land, the standard ballasted track can be shored up with additional material if required. However, tunnel, bridges and viaduct sections incorporate non-ballasted track on a concrete base, and in areas sensitive to noise pollution, floating slab track is used to cut noise and vibration.

The high frequency of services along the Airport Express and Lantau lines places particularly heavy demands on its infrastructure. A British company is playing a prominent role in ensuring that the line is kept in as good a running order as possible. AEA Technology Rail, based in Derby, UK, has a £100,000 deal to create a computer model for the maintenance of the track geometry, which will study the ballast along the 35km line, assess how it behaves in daily use and automatically develop a maintenance plan for the future. Another British connection exists in the train-washing system supplied by BWI Dawson of West Yorkshire for the rolling stock serving both lines.

ROLLING STOCK

The contract for new trains stipulated two distinct types of rolling stock for each service. However, the trains share a common body design. They are built by joint partners Adtranz and CAF, the former supplying traction and control equipment and a cab simulator for training purposes, and the latter the car bodies, bogies, interior fittings, air conditioning and auxiliary equipment. The trains were assembled in Spain, where static testing was also carried out, while final acceptance took place in Hong Kong.

The Airport Express line is served by a fleet of eleven seven-car trains whose facilities include a baggage car to carry luggage checked in at Hong Kong Central or Kowloon stations. They also have upholstered seats, carpets and luggage racks. Seat-back television screens provide up-to-date information on flights, MTR services and tourist information.

The Lantau line’s fleet comprises twelve trains seating a total of 336 passengers with standing room for 264 more in each car.

SIGNALLING AND COMMUNICATIONS

Signalling comprises three fully integrated system packages. Trains are supervised automatically from a main control centre, while their movements are controlled and constantly monitored by a transmission-based, automatic train control system and computer-controlled interlocking.

Stations are fitted with state-of-the-art communication and monitoring systems, including integrated passenger information displays to provide up-to-the-minute travel information. Train drivers have two-way communication with their main control centre in the event of emergencies.

Easy-to-use ticket machines and automatic fare collection equipment has also been sourced from the UK. Passengers use touch-screens to select their tickets and payment is by notes, coins or credit card.

THE FUTURE

When fully operational, the Airport Express link and Lantau line are expected to carry around 250,000 passengers a day.

In order to cater for this anticipated growth, the trains are capable of being strengthened from seven to ten cars, boosting capacity by around 50%. The signalling system is capable of handling a greater service frequency than the initial eight-minute interval. Ultimately, this could be increased to one train every four-and-a-half minutes.