Hong Kong Railway Operator Cuts Tunnel Inspection Time By Two-Thirds With Automated Drones

Hong Kong’s MTR Corporation is testing automated drones to inspect railway tunnels, slashing inspection times from 30 minutes to less than 10 minutes per kilometer. The trial, conducted in the tunnel between Admiralty and Exhibition Centre stations on the East Rail line, is part of Hong Kong’s ambitious 38-project regulatory sandbox program designed to accelerate commercial drone adoption.

The efficiency gains highlight how Asia-Pacific regulators are outpacing the United States in implementing practical beyond visual line of sight (BVLOS) operations for infrastructure inspection. While the FAA grapples with its controversial Part 108 rulemaking, Hong Kong launched its Low-Altitude Economy Regulatory Sandbox in March 2025 and already has dozens of projects collecting real-world operational data.

Automated Platform Enables Hands-Free Tunnel Inspections

The MTR Corporation operates the drones on a platform that allows them to complete inspection tasks automatically following programmable routes, according to the South China Morning Post. This automation eliminates the need for manual piloting in the confined, GPS-denied environment of railway tunnels.

Chan Hing-keung, the MTR Corp’s chief of operations for engineering service and innovation, explained the dramatic time savings to reporters. “We would like to make use of the mobility of drones to help our [staff] to carry out some repetitive tasks,” Chan said on Thursday.

Chan noted that manually inspecting one kilometer (0.6 miles) of tunnel typically took workers 30 minutes, while drones completed the same distance in less than 10 minutes. The drones check for critical infrastructure issues including water seepage, falling concrete, and whether access doors are properly closed.

Construction Zone Marking And Multi-Mission Capabilities

Beyond defect detection, the MTR is testing drone capabilities for placing red flashing lights to mark areas undergoing construction work. This application addresses a significant operational challenge for the rail operator.

“The flying velocity of the drones is faster than the working speed of a manual operator such that the time saving of this repetitive work is quite significant,” Chan explained. The drones travel at approximately 2.5 meters per second (8.2 feet per second) when placing warning lights, whereas workers walk at roughly one meter per second (3.3 feet per second).

“The speed is more than double,” Chan said. “Every night we have more than 200 construction projects after we suspend train services; we need flashing red lights at every section where there is construction work.”

“The longer the section, the more time we save. This gives us more time to do our repair and maintenance work,” he added.

Hong Kong’s Regulatory Sandbox Drives Innovation

The MTR trial represents one of 38 “sandbox” projects launched by Hong Kong authorities to promote commercial drone usage. The sandbox approach provides a controlled regulatory environment where companies can test new drone applications while government officials gather safety data and develop appropriate rules.

A sandbox in this context refers to a space where new technology can be tested in a pilot scheme under relaxed restrictions. Hong Kong’s Low-Altitude Economy Regulatory Sandbox, launched in March 2025, approved 38 projects from 72 applications spanning emergency rescue, logistics delivery, infrastructure inspection, and surveillance applications.

The MTR Corporation partnered with Traffic Control Technology on this initiative, establishing a Low-altitude Rail Research Center at Hong Kong Science Park on April 1, 2025. About 200 drone flights had been carried out as of September, with the trial scheduled to run from June through December 2025.

Expansion Plans For Open Rail Sections

The tests in the confined tunnel environment have proceeded satisfactorily, according to the rail giant. The MTR now plans to apply to authorities to expand testing to cover open sections of the East Rail line, potentially around Sheung Shui station.

Operating in open rail sections presents different regulatory challenges than confined tunnel operations.

“For the open sections, we would strictly follow the demands of the Civil Aviation Department,” Chan said. “We have different considerations if we are flying drones on the open section of our railway network, which include the distance of our drones to nearby buildings, were we to be flying near our power stations or high voltage power lines,” he explained.

Chan emphasized that emergency plans would be developed and testing would only occur once the company was familiar with every aspect of the project. The trial represented a partnership between the corporation and Traffic Control Technology, with both companies working to advance pilot projects under the regulatory sandbox framework.

DroneXL’s Take

Hong Kong’s regulatory sandbox approach offers a compelling alternative to the FAA’s troubled Part 108 rulemaking process. While American drone operators have spent years waiting for practical BVLOS regulations, Hong Kong launched its program in March 2025 and already has 38 projects generating operational data across multiple sectors.

The MTR tunnel inspection trial is particularly significant because it tackles one of the most challenging BVLOS applications: confined spaces with no GPS signal. These are exactly the environments where drones provide the most dramatic safety and efficiency improvements, yet they remain largely off-limits to U.S. operators without expensive, time-consuming waivers.

DroneXL has extensively covered railway inspection applications, from TrackSense’s automated track monitoring in Saskatchewan to BNSF Railway’s pioneering work with Skydio. The technology clearly works and delivers substantial benefits. The question is whether regulators will enable its deployment at scale.

Hong Kong’s sandbox model—test first, regulate later based on real data—stands in stark contrast to the FAA’s approach of attempting to write comprehensive rules before allowing meaningful experimentation. The MTR’s success in cutting inspection times by two-thirds while maintaining safety suggests the Asia-Pacific regulatory philosophy may be winning this race. We’ve seen this pattern before in Hong Kong with police drone patrols and building inspections—the city moves fast on practical applications while maintaining safety oversight.

As China’s broader low-altitude economy initiative targets $486 billion by 2035, Western regulators might want to pay attention. Innovation doesn’t wait for perfect regulations, and neither do competing economies.

What do you think about Hong Kong’s sandbox approach to drone regulations? Share your thoughts in the comments below.