TriMet gives flight to drone-enhanced inspections of MAX infrastructure

July 21, 2021
The pilot project will test a drone’s effectiveness inspecting overhead wires and bridges.

TriMet is launching a pilot project this month to get a new view of its infrastructure and help in the assessment of maintenance needs.

In the final week of July, TriMet will begin using a small drone to enhance the way it inspect the parts of the system that are either high up, like the overhead wires that power MAX trains, or difficult to reach, such as the undersides of bridges. TriMet plans to use this pilot project to assess whether the full-time use of a drone would improve the analysis of the MAX system.

Keeping staff safer and trains moving faster are also priorities, as crews regularly inspect the infrastructure of light rail by walking the tracks during service. This results in trains slowing down through these areas.

The first public use of the drone will be July 27, to assist with annual inspection of the MAX components on the Steel Bridge. This will allow crews to get an up-close, bird’s eye view of light-rail infrastructure on the bridge without having to send crews up a structure that’s more than 100-years old.

Crews will follow that work up with an inspection of Portland Streetcar’s overhead wires near Portland State University on July 29, and then the MAX overhead wires at Southwest Morrison and Yamhill on July 30.

In the works for more than two years, the drone inspection pilot project is a way to use advances in technology to better maintain the reliability of the MAX system. When there are issues with the overhead wires, it can result in disruptions as crews repair the damage.

TriMet does not plan to use the drone to replace the manual inspections that crews already regularly perform from the ground. Crews conduct these by walking the tracks and using binoculars to view the wires above. The team responsible for the overhead wire system is made up of 11 employees and two managers. However, using a drone means staff will be spending less time directly on the tracks or using boom trucks to reach elevated areas, creating a safer work environment.

“We’re taking inspections to a new level by taking to the air,” TriMet Maintenance of Way Coordinator Matt Baccitich said. “We think the program can grow with the agency as we find more ways to use the drone, not just to inspect things in the right-of-way, but also our facilities or other places that are difficult to access.”

The drone will allow inspectors to look directly at, or straight down, on parts of the system that otherwise couldn’t be inspected without stopping trains. The images—both still and video—will be collected and analyzed over time. This visual history has the potential to allow crews to track wear and tear and help make predictions about where issues may arise in the future.

The Federal Aviation Administration (FAA) limits commercial drone flights to a ceiling of 400 feet above the ground, and within line-of-sight of the pilot. TriMet’s drone will fly far below that, as the highest point in the system, the top of the Tilikum Crossing, is about 200 feet above the Willamette River. Currently, TriMet has one licensed drone operator who’s in contact with the FAA to ensure compliance with all airspace regulations.

Maintaining the system’s durability

The drone will fly missions until the weather changes this fall. Once that happens, the information and data collected will be reviewed, and the goals of the pilot project evaluated, to make a decision about moving forward on a full program.

TriMet’s light-rail system is made up of five lines, covering 60 miles in three counties. Some parts of the MAX system are about 35-years old and require routine inspections. Transit assets are evaluated on a regular basis and replaced and repaired as necessary to keep them in a state of good repair. Walking inspections of the system are currently performed monthly.