Light Signal Clearance Surface (Aviation)

Available with Aviation Airports license.

Available with Aviation Charting license.

Summary

Creates a Light Signal Clearance Surface (LSCS) based on the FAA Engineering Brief (EB) 95.

A LSCS determines which objects are vertical obstructions. An object is considered as vertical obstruction if it penetrates the LSCS. Surfaces are used to support planning and design activities.

Usage

• The Input Runway Features parameter must be z-enabled.

• This tool creates the Obstruction Identification Surface (OIS) in an existing polygon or multipatch feature class. It can also be generated in an existing polygon shapefile. If a feature class is selected for Target OIS Features, it must have a vertical spatial reference.

• OIS tools are flexible and accept a variety of input and output feature class types. For more information, see the OIS Input and Output schemas.

• The Input Airport Control Point Feature parameter can be used to supply x-, y-, and z-geometry for displaced threshold features. If displaced thresholds are included, surfaces will be constructed based on their x-, y-, and z-geometry instead of their corresponding runway feature endpoint.

Parameters

Dialog

Label	Explanation	Data Type
Input Runway Features	The input runway dataset. The feature class must be z-enabled and contain polylines.	Feature Layer
Target OIS Features	The target feature class that will contain the generated obstruction identification surfaces.	Feature Layer
Runway Direction (Optional)	Specifies the end of the runway where the approach surface will be created. High Runway End Designator— The approach surface will be created at the high end of the runway. This is the default. Low Runway End Designator—The approach surface will be created at the low end of the runway.	String
Length (Optional)	The length of the surface in miles. The default value is 8.	Double
Divergence (Optional)	The divergence of the surface in degrees. The default value is 14.	Double
Slope (Optional)	The slope of the surface in degrees. The default value is 1.	Double
Distance From Threshold (Optional)	The distance from the threshold in feet. The default value is 1000.	Double
First PAPI Light (Optional)	The location of the first precision approach path indicator. The default value is 60.	Double
Last PAPI Light (Optional)	The location of the last precision approach path indicator. The default value is 120.	Double
Start Height (Optional)	The start height of the surface. The default value is 35.	Double
Input Airport Control Point Feature (Optional)	Supplies x-, y-, and z-geometry for displaced threshold features. If displaced thresholds are included, surfaces will be constructed based on their x-, y-, and z-geometry instead of their corresponding runway feature endpoint.	Feature Layer
Surface Position (Optional)	Specifies the position of the precision approach path indicator (PAPI) lights on either side of a runway. The position of the PAPI lights will be used to determine the position of the output surface. Generate surface on left approach side of the runway—PAPI lights are on the left approach side of the runway. The surface will generate on the left approach side of the runway. This is the default. Generate surface on right approach side of the runway—PAPI lights are on the right approach side of the runway. The surface will generate on the right approach side of the runway.	String

Derived Output

Label	Explanation	Data Type
Output OIS Features	The updated feature class containing the generated Obstruction Identification Surface.	Feature Layer

Python

arcpy.aviation.LightSignalClearanceSurface(in_features, target, {runway_direction}, {length}, {divergence}, {slope}, {distance_from_threshold}, {first_papi_light}, {last_papi_light}, {start_height}, {airport_control_point_feature_class}, {surface_position})

Name	Explanation	Data Type
in_features	The input runway dataset. The feature class must be z-enabled and contain polylines.	Feature Layer
target	The target feature class that will contain the generated obstruction identification surfaces.	Feature Layer
runway_direction (Optional)	Specifies the end of the runway where the approach surface will be created. HIGH_RUNWAY_END_DESIGNATOR— The approach surface will be created at the high end of the runway. This is the default. LOW_RUNWAY_END_DESIGNATOR—The approach surface will be created at the low end of the runway.	String
length (Optional)	The length of the surface in miles. The default value is 8.	Double
divergence (Optional)	The divergence of the surface in degrees. The default value is 14.	Double
slope (Optional)	The slope of the surface in degrees. The default value is 1.	Double
distance_from_threshold (Optional)	The distance from the threshold in feet. The default value is 1000.	Double
first_papi_light (Optional)	The location of the first precision approach path indicator. The default value is 60.	Double
last_papi_light (Optional)	The location of the last precision approach path indicator. The default value is 120.	Double
start_height (Optional)	The start height of the surface. The default value is 35.	Double
airport_control_point_feature_class (Optional)	Supplies x-, y-, and z-geometry for displaced threshold features. If displaced thresholds are included, surfaces will be constructed based on their x-, y-, and z-geometry instead of their corresponding runway feature endpoint.	Feature Layer
surface_position (Optional)	Specifies the position of the precision approach path indicator (PAPI) lights on either side of a runway. The position of the PAPI lights will be used to determine the position of the output surface. SURFACE_GENERATED_ON_LEFT—PAPI lights are on the left approach side of the runway. The surface will generate on the left approach side of the runway. This is the default. SURFACE_GENERATED_ON_RIGHT—PAPI lights are on the right approach side of the runway. The surface will generate on the right approach side of the runway.	String

Derived Output

Name	Explanation	Data Type
derived_outfeatureclass	The updated feature class containing the generated Obstruction Identification Surface.	Feature Layer

Code sample

LightSignalClearanceSurface example (stand-alone script)

The following Python window script demonstrates how to use the LightSignalClearanceSurface tool.

import arcpy

arcpy.CheckOutExtension("Airports")

# Input Runway Feature Class
inFeatures = r"C:\data\ois.gdb\RunwayCenterline"

# Feature class that will contain the OIS surface
outFeatures= r"C:\data\ois.gdb\ObstructionIdSurface"

# Define surface dimensions
runway = "HIGH_RUNWAY_END_DESIGNATOR"
length = 8
divergence = 14
slope = 1
distance_from_threshold = 1000
first_papi_light = 60
last_papi_light = 120
start_height = 35

# Generate Light Signal Clearance Surface
arcpy.aviation.LightSignalClearanceSurface(inFeatures, outFeatures, runway,
                                           length, divergence, slope,
                                           distance_from_threshold,
                                           first_papi_light, last_papi_light,
                                           start_height)

arcpy.CheckInExtension("Airports")

Environments

This tool does not use any geoprocessing environments.

Licensing information

• Basic: No
• Standard: Requires Airports or ArcGIS Aviation Charting
• Advanced: Requires Airports or ArcGIS Aviation Charting