Minimum descent altitude (MDA)

Definitions

• The lowest altitude (in feet MSL) to which descent is authorized on final approach, or during circle-to-land maneuvering in execution of a nonprecision approach.
• The lowest altitude, expressed in feet above mean sea level, to which descent is authorized on final approach or during circle-to-land maneuvering in execution of a standard instrument approach procedure where no electronic glide slope is provided.

References

• Instrument Flying Handbook, Federal Aviation Administration, 2014
• Instrument Procedures Handbook, Federal Aviation Administration, 2017