Definition
Geographic position markings are pink circles painted on taxiway centerlines at specified intervals during low-visibility operations. Each marking is identified by a number, or a number and letter, displayed in black on a white background within the pink circle, and serves as a hold point or reporting position for aircraft and vehicles taxiing under Surface Movement Guidance Control System (SMGCS) procedures.
Plain English
Painted pink circles on the taxiway, each with its own number, that pilots use as checkpoints when visibility is very low. They tell ground control exactly where you are on the airport surface and give you defined places to stop.
Context Anchor
Seen while taxiing at certain larger airports, especially when the airport uses a special low-visibility taxi plan.
Derivation
"Geographic position" means "a specific location on the ground." The phrase is used because each pink circle is tied to one identified spot on the airport, giving controllers and pilots a shared way to refer to where an aircraft actually is during low visibility.
Why Pilots Care
Enables precise position reporting that reduces runway incursions and keeps aircraft moving safely when visibility is poor.
Analogy
They work like numbered location spots in a large parking garage: instead of guessing where you are, you can refer to the exact marked spot.
Intuition Check
Do not assume this means any airport marking that happens to be on the ground. In this FAA context, it means a specific location-identification marking used to show an exact position on the airport surface.
Example Sentence 1
Ground instructed the crew to taxi via Alpha and hold short at geographic position 4.
Example Sentence 2
Controllers use geographic position markings to track aircraft locations accurately during SMGCS operations.