UnplannedHolding
urn:aero:airm:1.0.0:ConceptualModel:Subjects:AirspaceInfrastructure:RouteAndProcedure:UnplannedHolding
A specific holding procedure requested at an en-route fix on airway or route radials, bearings, or courses.
Source:
EUROCONTROL-FAA AIXM v.5.1,