What is the purpose of a displaced threshold?

A displaced threshold serves a critical role in improving the safety and functionality of runways. When a runway has a displaced threshold, it essentially shifts the point where the runway begins for landing purposes further down the runway. This means that pilots are directed to land their aircraft farther down the runway than its physical start.

This situation can occur for various reasons, such as the presence of obstacles that require a longer approach to ensure safe landing without risk of collision or obstruction, or to facilitate certain types of operations like noise abatement. It’s important to understand that while takeoff can occur from the entire length of the runway, the actual landing point must respect this displaced threshold specification for landing procedures.

The other choices describe scenarios that do not accurately represent the function of a displaced threshold. For instance, a displaced threshold does not extend the physical length of the runway for takeoff; it merely creates a restriction on landing. Furthermore, the idea of marking prohibited taxiing areas or indicating runway extensions does not align with the defined purpose of a displaced threshold within airport operations.