The inspection of MRT tunnels, currently conducted manually by workers, could soon be done faster and safer with the use of drones.

Yesterday, the Land Transport Authority issued a request for information (RFI) on using drones and unmanned vehicles (UVs) to inspect road and rail tunnels.

Currently, these inspections - aimed at detecting problems such as cracks or water leakage and assessing whether maintenance is required on tunnel structures - are labour-intensive as workers physically comb the tunnels, said the LTA.

It added that inspecting rail tunnels is challenging as workers have only three hours to conduct the checks at night after the end of passenger services.

Organisations participating in the RFI will design and develop a trial for the use of drones to inspect MRT tunnels, which will involve 360-degree video mapping and the use of software to detect the location of defects.

Participants may also develop a trial for inspecting road tunnels using drones, UVs or other technologies.

The authority added that the use of such technology will improve the accuracy of inspections and allow engineers to focus on analysing the data captured.

Last November, the Ministry of Transport awarded a master contract to Aetos Security Management, Avetics Global and CWT Aerospace Services to provide drones to public agencies, including the LTA.

The LTA is already conducting a year-long trial of the use of drones to monitor progress at 10 worksites for the upcoming Thomson-East Coast MRT line. The RFI is an expansion of these trials, said the authority.

It added that if found effective, the technologies could be "fully deployed" within the next five years.

While it could be difficult to navigate drones in tunnels, their use will help increase productivity, said robotics specialist Foong Shaohui from the Singapore University of Technology and Design. "A drone won't get tired or make mistakes during inspections," he added.