With two lines covering a total of 55 km and 23 stations the BTS Skytrain first opened in 1999. The Sukhumvit Line runs North to East and the Silom Line interconnects at Siam station and serves the central business district of Bangkok.
Bombardier Transportation was awarded a contract to perform the resignalling of the whole BTS Skytrain route, without disruption, during continued operations. The first stage of this was the Silom line extension.
On the 15th of May 2009 the BTS Skytrain Silom Line Extension opened. The Silom Line Extension is the first of three deliveries for the BTS Skytrain and its operator, the Bangkok Metropolitan Administration (BMA) and incorporates the CITYFLO 450 communication based train control (CBTC) system from Bombardier Transportation.
The complete installation includes eight stations on the Silom Line and 16 stations on the Sukhumvit Line and involves 49 trains of four different vehicle types. This includes 12 newly built 4-car EMUs supplied by the Changchun Railway Vehicles in China and based on the Bombardier MOVIA, which are being provided to ease current overcrowding on the BTS lines.
The communication based train control (CBTC) solution of the CITYFLO 450 system enables rail traffic headways to be reduced enabling higher numbers of passengers to be transported. The system does not require track circuits and uses balises for position referencing and precision stopping.
The solution is based on the successful and widely deployed Bombardier CITYFLO 350 system and inherits all the proven worldwide operational performance. Semiautomatic train operation (STO) functionality is provided with energy saving performance and the CBTC enables integration of for example SCADA (supervisory control and data acquisition), PIDs (passenger information displays) and other peripheral systems as needed for a complete train control system.