Drones speed up bridge inspections

Published 9:44 am Thursday, October 8, 2020

Tyrrell County has at least a dozen state-maintained highway bridges, which require periodic inspection to assure their safety. Each inspection can slow down or even re-route traffic temporarily. Now, something new is on the scene.

Drones are the N.C. Department of Transportation’s newest tool in maintaining the safety of the state’s bridges and other infrastructure.

The Federal Aviation Administration on Oct. 2 approved a waiver that allows NCDOT to operate Unmanned Aircraft Systems beyond visual line of sight while conducting bridge inspections. NCDOT thus became the first state transportation agency to have been awarded such a waiver.

“We are pleased to be leading the way with this fantastic new tool,” said North Carolina’s Secretary of Transportation Eric Boyette. “Safety is our top priority at NCDOT, and this new system will enable us to complete inspections while better protecting our inspectors and the integrity of our bridges.”

Skydio is the largest U.S.-based drone maker. Its drones are powered by on-board artificial intelligence that enables each craft to avoid obstacles in complex areas that lack a reliable GPS signal, such as the trusses beneath bridges.

Ben Spain, the NCDOT’s UAS program manager, said drones have been used since 2016 to conduct bridge inspections. But by enabling the drones to move beyond the pilot’s line of sight, the inspections will be able to collect more high-resolution images in difficult to see places so inspectors can better analyze the bridge’s integrity and identify possible problems.

“Inspectors will collect images using the drone instead of a snooper truck or having to suspend the inspector from the bridge,” Spain added. “They’ll be able to do these inspections quickly with minimal impacts to the traveling public, like not having to close lanes of traffic for as long.”