DEGRADED –Checked, and there is a problem. Always visible, every zoom, every tier.
NOMINAL –Checked, and it is fine — with the check time on the marker.
UNKNOWN –A feed exists; this reading is stale or absent. Hollow, never teal.
NO FEED AT ALL –No commercial feed exists for this field. Marked ×.
An airport we did not check is never drawn as an airport that is fine.
Advisory — a separate axis
ADVISORY IN FORCE –A risk judgement by an issuer that does not control the airspace. A ring
around the fact — it never recolours it.
SCOPE UNKNOWN –Level or scope not established. Never an airfield-specific all-clear —
and the common case, so a missing violet ring means nothing on its own.
An airport can be open under do-not-fly, or closed in a calm country.
The two axes are never collapsed into one colour.
Freshness — when did we last look
FRESH –Checked in the last 45 min — three sweeps of the 15-minute clock.
AGING –45 min to 6 h old. Still a check; no longer a current one.
STALE –Older than 6 h. Faded, and its label drops to slate.
NO CHECK TIME HELD –Neither a sweep nor an operational check carries a time for this field.
Already hollow — there is nothing to fade.
Age fades a NOMINAL disc only, because “it was fine” is the one
claim here with a clock on it. It stays a filled teal disc at every age — a faded disc is
never a hollow ring. A degraded field is never faded: you do not dim a problem for being old.
Monitor tier — the cadence, in words
loading…
Tier drives marker size and the zoom a field appears at — but a degraded
or closed field is never hidden to tidy the map.