Class - Obstruction

<< object >> Logical View.AIXM.AIXM Features.Shared.Surface Assessment
<<object>> [FAA 8260.3] The highest airspace, obstacle or terrain relative to a prescribed plane within a specified area. NOTE: In precision approach procedures where obstacles penetrate the approach surface, the controlling obstacle is the one which results in the requirement for the highest decision height (DH).

List of attributes

Name Data Type Definition    
requiredClearance ValDistanceType Required altitude adjustment above any obstacle or terrain within a defined safety buffer region. The safety buffer allows for errors in the air and in the accuracy of data such as obstacle accuracy. This together with other adjustments (human factor adjustments, lighting adjustments, altimeter adjustments, etc). give the minimum altitude.    
minimumAltitude ValDistanceVerticalType The value of the minimum obstacle clearance altitude.    
surfacePenetration CodeYesNoType A code indicating whether the controlling obstacle penetrates the assessment surfaces. Rule: if surfacePenetration is "NO", then slopePenetration will not have a value.    
slopePenetration ValAngleType A value calculated by dividing 102.0 (a constant) with the angle of the glidepath    
controlling CodeYesNoType Indication whether it is a "controlling obstruction" for the associated ObstacleAssessmentArea.    
closeIn CodeYesNoType "Close-In Obstacles" are those that would penetrate the 40:1 OCS and would require a climb gradient to 200 feet or less above the departure end of runway. So if an aircraft climbs at the minimum standard 200 feet per NM, "Close-In Obstacles" are those within 1 NM from the end of the runway.    

Navigable associations to Obstruction

From Association Multiplicity Role To Role description
ObstacleAssessmentArea isResolvedBy 0..* significantObstacle The obstacle that controls the altitude definition of the assessment area would penetrate the 40:1 OCS  
TerminalArrivalAreaSector isResolvedBy 0..* significantObstacle The obstacle that controls the altitude definition of the sector.  
NavigationAreaSector isResolvedBy 0..* significantObstacle The obstacle that controls the altitude definition of the sector or would penetrate the 40:1 OCS.  
SafeAltitudeAreaSector isResolvedBy 0..* significantObstacle The obstacle that controls the altitude definition of the sector.