THE article ("Reliability of MRT key to having fewer cars on roads"; Feb 13) alleged that Singapore's MRT system is less reliable than the New York City Subway, through a comparison that our MRT had one breakdown every 120,000km while New York's had one every 260,000km. This is incorrect and unfortunately was repeated in the commentary ("Public transport: No. 1 in the world?"; last Saturday).
New York's Metropolitan Transportation Authority measures train reliability using car-kilometres whereas Singapore uses train-kilometres. On Singapore's six- and three-car systems, one train-km is equivalent to six car-km and three car-km respectively.
If our six-car train encounters a fault after 100,000km, it would be reflected in our statistics as having failed once after 100,000 train-km. However, if we convert this to car-km, the six-car train would have experienced a fault after 600,000 car-km. Similarly, for a three-car train that encounters a fault after 100,000 train-km, it would be reflected as having failed after 300,000 car-km.
Hence, comparing like with like, Singapore's rail reliability would be more, not less, reliable than New York's by a considerable margin. Our MRT network experienced one delay longer than five minutes for every 456,000 car-km operated last year, compared with New York's one in 247,000 car-km.
Notwithstanding this, we acknowledge that there is work to be done to improve our rail network reliability. SMRT and SBS Transit have ramped up their engineering capabilities and processes, hired more engineers and significantly increased investment in maintenance.
The Land Transport Authority is also working with the two operators to strengthen their maintenance regimes to actively monitor the condition of their assets, predict where problems are most likely to occur, and take pre-emptive steps where required.
Helen Lim (Ms)
Director, Media Relations
Land Transport Authority