In the Distance Method for determining VDP, how is distance from the runway estimated?

• A. (MDA in AGL x 3) / 1,000
• B. MDA in AGL / 2
• C. (MDA in AGL x 2) / 1,000
• D. MDA in AGL x 3,000

Answer: (A)

The Distance Method uses the height at which you level off on the approach (MDA) to estimate where along the final approach you would reach the runway if you descended from that MDA. It’s a quick rule of thumb for non-precision approaches to locate the visual descent point (VDP) so you know where to begin a normal descent to the runway when the required visual references are available.

The distance from the runway is estimated in nautical miles by taking the MDA value in feet AGL, multiplying by 3, and dividing by 1,000. In other words, distance (NM) ≈ (MDA in feet AGL × 3) / 1000. This gives a practical position along the final approach course where you would be at MDA and can start descending toward the runway if you can see the airport and meet the visibility requirements.

For example, if the MDA is 600 feet AGL, the estimated distance to the VDP would be (600 × 3) / 1000 = 1.8 NM from the threshold. Remember to use MDA as AGL; if you have MDA in MSL, subtract the field elevation to convert to AGL before applying the formula.