Aerotrain (KLIA)
The Aerotrain is an automated people mover (APM) system located within the Kuala Lumpur International Airport in Malaysia. Opened in 1998 along with the airport, the Aerotrain system consists of two stations, one in the Main Terminal Building and the other in Satellite Building A. The system is the only means of transport for passengers between the two terminals. Upgrading works on the Aerotrain had caused the service to be suspended between 1 November 2010 and 15 March 2011. Passengers were transferred between the Main Terminal Building and the Satellite Building by bus shuttles during the upgrading period . General information. The Aerotrain is fully automated and driverless. Usually, two trains ply between the two stations. In accordance with the Spanish solution, when the train reaches the platform, the exit doors will open first for passengers to disembark, after which the entrance door on the other side will open. Part of the train track goes underground to cross the taxiway. The ride between the Main Terminal Building and Satellite Terminal A takes about 2.5 minutes. The Aerotrain supported various operating modes such as Synchronized Double Shuttle Mode, Offset synchronized Double Shuttle Mode, Unsynchronized Double Shuttle Mode, Single Shuttle Mode , On-Call Mode, Test Train Mode and Out Of Service Mode. The Aerotrain has 4 major sub-systems, namely the Central Control System, Vehicle System, Station Automatic Train Operation (ATO) System and Power Distribution System (PDS). The trains have an operating speed of with a 3-phase AC 600V power supply at 50 Hz. A DC electric motor (model number: 1460-P4, controlled by a thyristor drive) constitutes the propulsion system of the trains. The maintenance of the Aerotrain is scheduled at 10am-12pm and 12am-5am everyday, when only one of the trains will be running for operation and the other  one will undergo maintenance works and safety checks. The frequency of the train decreases from every 2⁄ minutes to every 5 minutes during the maintenance periods. Rolling stock. The rolling stock is manufactured by Adtranz (merged with Bombardier Transportation in 2001) and comprises 3 CX-100 trains with 3 cars per train (originally 2 cars), of which each car has a capacity of 249. On 15 March 2011, a new train was added to the fleet which is known as Train 3. The addition is made to cover the shortfall of the Aerotrain system when either Train 1 or Train 2  is scheduled for an overhaul programme. The overhaul programme is necessary as both Train 1 and Train 2 has been in use for 13 years. Incidents. On 25 December 2017, one of the trains broke down in between the two terminals and a detrainment was carried out. This left the aerotrain running on a single train and free shuttle buses were provided.