Definition
Navigation information that tells the pilot both the correct left-right path (lateral) and the correct up-down path (vertical) to fly during an approach. Lateral guidance keeps the aircraft aligned with the runway centerline, while vertical guidance keeps it on the correct descent path to the runway.
Plain English
Information that tells you whether you are too far left or right, and whether you are too high or too low, as you fly toward the runway.
Context Anchor
Seen in instrument approach discussions, especially when describing how a microwave landing system helps guide an aircraft to a runway.
Derivation
Lateral comes from the Latin lateralis, meaning 'of the side.' Vertical comes from the Latin verticalis, meaning 'overhead' or 'upright.' Together they describe guidance in two directions: side-to-side and up-and-down.
Why Pilots Care
Accurate lateral and vertical guidance allows safe landings in low visibility that would otherwise be impossible.
Grounding Statement
Picture the aircraft needing to stay centered with the runway while also coming down along a safe slope toward it.
Intuition Check
Do not read "guidance" here as general advice. In this context, it means specific navigation information that shows where the aircraft is in relation to the correct path.
Example Sentence 1
MLS provides both lateral and vertical guidance, allowing the pilot to fly a precise approach to the runway.
Example Sentence 2
When the ILS was out of service, the crew used MLS lateral and vertical guidance to complete the landing.