Definition
Visual markings on objects such as towers, stacks, buildings, and other tall structures that make them clearly visible to pilots during daylight hours. Daymarks typically consist of high-contrast paint patterns — most commonly alternating bands of aviation orange and white — applied to obstructions that could pose a hazard to low-flying aircraft.
Plain English
Bright paint patterns on tall structures that make them easy to see from the air during the day, so pilots can spot and avoid them.
Context Anchor
Seen in discussions of visual marking for airports, navigation aids, towers, wires, and other objects pilots may need to identify or avoid in daylight.
Derivation
From 'day' plus 'mark' — literally a marking intended to be seen by day. The term distinguishes them from obstruction lights, which serve the same purpose at night.
Why Pilots Care
Daymarks are one of the main visual cues for spotting and avoiding obstructions during VFR flight, especially at low altitudes during takeoff, approach, or pipeline and powerline patrols.
Grounding Statement
A daymark is a daytime visual cue: if you can see the marking clearly in daylight, it is doing its job.
Intuition Check
Do not think of daymarks as calendar marks or time records. In aviation, daymarks are physical visual markings used for daytime recognition.
Example Sentence 1
The tall radio tower east of the field had bright orange and white daymarks, making it easy to spot on approach.
Example Sentence 2
Daymarks on the chart helped the pilot maintain course over the lake without instruments.