ATC regulations require control towers to maintain a visibility checkpoint chart or list of visibility markers posted in the tower. Upon request, which entity will provide assistance to help prepare a chart or markers for determining tower visibility?

• A. Control Tower Visibility Aids.
• B. EUs will provide whatever assistance is necessary to help prepare a chart or markers of suitable objects for determining tower visibility.
• C. Aircraft Mishap.
• D. Supplementary Data for an Inactive or Parallel Runway.

Answer: (B)

The main idea here is that maintaining a consistent visibility reference in the control tower—through a chart or a set of known visibility markers—requires technical support from the unit responsible for engineering and standards in airfield operations. When the tower needs to prepare or update that chart or the markers, Engineering Units provide the necessary assistance: they identify objects that can serve as reliable visibility references, help determine appropriate distances and measurements, and assist in compiling and documenting the chart so it meets established criteria. They coordinate with base engineers to ensure markers are safe, properly placed, and durable, and that the chart reflects current conditions. This engineering support is the professional resource designated for creating and maintaining accurate tower visibility references, which is why this option is the correct fit.