Plain English Meaning

Whether the wheels are down, up, or moving between those positions right now. The aircraft's warning systems check this to know if you are set up to land or still flying en route.

Full Definition

The current position of the landing gear — extended (down and locked), retracted (up and locked), or in transit between the two — as reported to the pilot by cockpit indicators and used as an input by terrain alerting systems to decide which warnings to issue.

Context Anchor

Seen in terrain alerting system discussions, especially when the system checks whether the aircraft is set up properly during descent and approach.