Whether you grew up taking joyrides with your family while at the airport or caught them passing by Jewel Changi Airport as you dined and shop there, the Skytrains are a big part of the Changi experience and hold a special place in many of our hearts.

With the pandemic derailing the travel plans of millions worldwide, Changi Journeys takes a behind-the-scenes look at what the 22 Skytrains have been up to and the work that goes into keeping them in good shape. 

Skytrain “Number 12” at the South Workshop near Terminal 3.

Overhaul works in progress

When we visited the inconspicuously located Skytrain South Workshop near Terminal 3 earlier this month, maintenance workers were removing the doors of a train. Key components of the train doors such as door rollers and sensors were being replaced as part of major overhaul works on 16 of the 22 Skytrains. 

New door rails, sensors, rollers and limit switches are installed to replace older parts that have been worn down through repeated use.

These 16 trains first came into operation in 2006 and are going through the second major overhaul works of their lifespans. These are works that the remaining newer six trains of the fleet, which have only been in service since 2019, will eventually go through.

Before the pandemic hit, the trains used to carry nearly 10,000 passengers per day and run from 5.00am to 2.30am daily. It is no surprise that the individual parts of the train get worn down due to regular use. According to the Engineering Management and Systems Planning team taking care of the trains, replacing these parts and others that have been damaged by passengers, is key to the reliability of the iconic Skytrains.

No free ride when it comes to maintenance

Replacing the major components of 16 trains is no easy task. The replacement work is arduous and extensive – from parts that we are familiar with such as doors, lights and floors, to those that are hidden away from sight, like brakes, batteries and traction motors.

Replacing sensors embedded in the black rubber strip of the train door.

Some of these parts require replacing because of damage unknowingly caused by passengers. For example, the sensors embedded in the rubber strips of the train doors get damaged when passengers pushing trolleys rush to enter a train when the doors are closing. The repeated impact of the metal trolleys hitting the doors causes the sensors to malfunction, requiring them to be replaced for safety.

But perhaps the most gruelling and technically-challenging job of all is to replace the undercarriage of the trains, called bogies. The bogies carry crucial components of a train, such as wheels, driving axles steering rods and suspensions.