If cords are visible on the main gear tire, what action is required?

When cords are visible on the main gear tire, it indicates a serious issue with the tire's integrity. The visibility of cords suggests that the tire is severely worn or damaged, compromising its ability to safely support the aircraft during operations. Therefore, notifying maintenance is the required action.

This step is crucial because maintenance personnel have the expertise and the tools to further assess the condition of the tire and determine appropriate corrective actions. Continuing to taxi or operating the aircraft with a compromised tire could lead to tire failure or other safety risks during flight operations. Inspecting the tire may seem prudent, but it's typically up to trained maintenance staff to perform such evaluations to ensure safety standards are met. Obtaining pilot approval in this context does not address the immediate need for professional maintenance intervention when visible damage is present.