The Missed Approach Point (MAP) on a precision approach is reached when the aircraft arrives at the decision height (DH) or decision altitude (DA) prescribed for that specific approach, while the aircraft is maintaining the glideslope.
Essentially, the MAP on a precision approach is not a geographical location as it is on a non-precision approach. Instead, it is a specific point in space, determined by the altitude the aircraft is at while intercepting the descent path provided by the Instrument Landing System (ILS), precision approach radar (PAR), or other comparable system.
Here's a breakdown:
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Decision Height (DH) or Decision Altitude (DA): This is the specified altitude in a precision approach at which a pilot must decide whether to continue the approach or initiate a missed approach if the required visual references (e.g., runway environment) are not visible.
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Glideslope: The glideslope provides vertical guidance, helping the aircraft descend at the correct angle towards the runway.
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MAP Determination: The MAP is determined when the aircraft, flying on the glideslope, reaches the published DH/DA. The pilot must make a decision at this point.
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Missed Approach Procedure: If the required visual references are not visible at the MAP (DH/DA), the pilot must immediately execute the published missed approach procedure.
In simpler terms: On a precision approach, you're constantly "at" the MAP from the Final Approach Fix (FAF) all the way down the glideslope. The actual "MAP" occurs when you reach the Decision Altitude/Height. If you don't see the runway environment at that altitude, you initiate the missed approach.
Key Differences from Non-Precision Approach MAP:
Unlike a non-precision approach, where the MAP is a specific geographical fix (e.g., a VOR station or a DME distance), the precision approach MAP is defined by altitude.
