Definition
A head-up display (HUD) is a transparent cockpit display, mounted in the pilot's forward line of sight, that projects flight information such as airspeed, altitude, attitude, heading, and flight path symbology onto a combiner glass so the pilot can read the data while still looking outside the aircraft. In CAT II and CAT III approach operations, HUDs are often certified as part of the approach guidance system and may allow lower minimums by presenting precise approach and landing cues directly in the pilot's external view.
Plain English
A clear screen sitting in front of the pilot that shows key flight information without blocking the view through the windshield. The pilot can see the runway and the instrument data at the same time, instead of looking down at the panel and back up.
Context Anchor
Seen in low-visibility approach and landing discussions, especially when an aircraft is approved to use this equipment during very low cloud or poor visibility.
Derivation
Called 'head-up' because the pilot keeps their head up and eyes forward, rather than looking 'head-down' at the instrument panel. The name describes the posture the display is designed to support.
Why Pilots Care
Reduces gaze shifts between instruments and the runway, improving safety in low-visibility landings.
Intuition Check
Do not read “head-up” as just meaning the display is mounted higher. In aviation, it means the pilot can keep looking forward while seeing the needed flight information.
Example Sentence 1
The captain briefed that the HUD would be used for the CAT III approach into the fog-bound airport.
Example Sentence 2
Head-up displays allow better situational awareness by superimposing symbology on the real-world view ahead.