ALD stands for which term in runway operations?

• A. Available Landing Distance (ALD)
• B. Available Landing Distance
• C. Approach Landing Distance
• D. Available Landing Data

Answer: (A)

The concept being tested is what distance is actually usable for landing on a runway. ALD stands for Available Landing Distance. It is the portion of the runway that can be used for touchdown and deceleration from the threshold to the end of the landing area, after any displaced threshold, stopways, or other restrictions are factored in. This distance is what pilots and dispatchers rely on for landing performance calculations and decision-making, ensuring the aircraft can land safely within the available space. It’s different from the full physical runway length and from takeoff-related distances. If a threshold is displaced or part of the runway can’t be used for landing for any reason, the ALD decreases accordingly.