DA vs MDA

In aviation, Minimum Descent Altitude (MDA) and Decision Altitude (DA) are different altitudes that pilots use during different types of approaches:

MDA

Used for non-precision approaches, MDA is the lowest altitude a pilot can descend to without visual references. Pilots must maintain MDA until they reach the Visual Descent Point (VDP) if the runway is visible, or until the Missed Approach Point (MAP) if it's not. Once at MDA, pilots level off and continue until they have the visual references needed to land, or until they reach the MAP and must execute a missed approach.

DA

Used for precision or precision-like approaches, DA is the altitude at which pilots decide whether to continue descending and land, or to execute a missed approach. Pilots make this decision based on visual cues or instrument indications as they descend on the glideslope. They may go slightly below DA while making their decision, but a clear area is required below DA. As the approach gets closer to DA without visual cues, the balance shifts more towards a missed approach.