What is a Visual Descent Point (VDP) and how is it calculated?

• A. The distance from the runway threshold to the VDP equals the AGL of the MDA divided by 300
• B. The VDP is the vertical distance above the runway at touchdown
• C. The VDP is the distance from the final approach fix to the runway threshold
• D. The VDP is the angle of descent from MDA to the runway

Answer: (A)

A Visual Descent Point is the point along the final approach course where you can begin a normal descent from the minimum descent altitude down to the runway, using a standard 3-degree path when you have the required visual references. The calculation uses how high the MDA is above the airport surface, because that vertical height determines how far you must travel horizontally to maintain a 3-degree descent.

The practical rule of thumb is: the distance from the runway threshold to the VDP (in nautical miles) is roughly equal to the height of the MDA above the airport (in feet) divided by 300. This comes from relating a 3-degree glide path to vertical drop versus horizontal distance, giving a convenient approximate value for planning the descent point. That’s why the option stating that the VDP distance equals the MDA above the airport (AGL) divided by 300 is the best choice.

This isn’t the vertical distance to touchdown, nor the distance from the final approach fix to the runway, and it isn’t the descent angle itself. The VDP is a point on the approach path defined by a distance from the threshold, determined by the height of the MDA above the airport.