To determine the required ceiling for a circling approach without a published ceiling, what is the appropriate method?

The appropriate method for determining the required ceiling for a circling approach when there is no published ceiling is to add 100 feet to the Height Above Airport (HAA) and then round up to the next hundred. This approach takes into account the necessary vertical clearance required for safe maneuvering during the circling phase of the approach.

The HAA gives pilots the minimum height above the airport they should maintain while circling to land. By adding an additional 100 feet, pilots are provided with a buffer that enhances safety during the transition from the approach to the landing phase. Rounding this figure to the next hundred simplifies the operational use of the ceiling requirement, making it easier for pilots to recall and apply during flight operations.

This method is in line with standard practices established in FAA regulations and guidelines, ensuring pilots have adequate altitude to perform the circling maneuver without risking conflicts with any obstructions or terrain around the airport. Other options may not accurately reflect the regulatory requirements or might not provide the necessary margin of safety outlined in appropriate aeronautical guidelines.