What does "MDA" stand for and when is it used?

"Minimum Descent Altitude" is the term represented by the acronym "MDA." It is specifically used during non-precision approaches to define the lowest altitude to which a pilot may descend in the approach phase without visual reference to the runway or the approaches' landing environment.

During a non-precision approach, once the pilot has reached the MDA, they must maintain that altitude until they either establish visual reference with the runway or reaches the decision point where they must execute a missed approach. The MDA provides pilots with a critical reference point to ensure safety during an approach where guidance systems do not offer precise vertical navigation, making it vital for safe landing maneuvers.

Understanding MDA is crucial for flight safety, especially in conditions with limited visibility or without the aid of an instrument landing system, as it helps pilots navigate safely through the final phases of approach and landing.