ALS stands for which term in aviation?

• A. Alternate Landing System
• B. Alignment Lighting Sequence
• C. Approach Lighting System
• D. Auto Landing Sensor

Answer: (C)

Approach Lighting System is a set of lights installed at the approach end of a runway to provide visual cues that help you transition from instrument flight to a visual landing, especially in low visibility or nighttime conditions. ALS stands for Approach Lighting System, the recognized term for this network of lights that typically includes sequenced flashing lights, crossbars, and other light bars extending outward from the threshold to help you judge runway alignment and distance.

The other phrases aren’t standard terms used in aviation lighting. So, the correct name is the one that describes a lighting system dedicated to guiding you on final approach and aligning with the runway.