FAA FAR 77 (Aeronautical)

Summary

Creates obstacle identification surfaces based on the FAA FAR 77 specification. These surfaces describe airspace segments that are clear of obstacles. The type, function, and dimension of a surface differs by runway classification. This tool creates surfaces as polygon features.

Usage

Syntax

FAAFAR77_Aeronautical (in_features, input_feature_sql, {input_clear_way}, input_runway_type, input_airport_elevation, input_ois_unit, input_ois_slope, primary_surface, primary_surface_length, primary_surface_width, conical_surface, conical_surface_slope, conical_surface_offset, horizontal_surface, horizontal_surface_radius, horizontal_surface_height, approach_surface, approach_surface_extendedwidth, first_section_length, first_section_slope, second_section_length, second_section_slope, transitional_surface, transition_surface_slope, output_feature_class)
ParameterExplanationData Type
in_features

The input runway dataset. The feature class must be polyline or polygon.

Feature Layer
input_feature_sql

A Structured Query Language (SQL) WHERE clause that selects a subset of features from in_features.

SQL Expression
input_clear_way
(Optional)

The length of the area at the end of the take-off run. An aircraft can make a portion of its initial climb over this area.

Double
input_runway_type

The runway classification of the Input Runway Features (in_features).

  • Utility visual approachA runway built for propeller aircraft not exceeding 12,500 pounds gross weight. Aircraft using the runway employ visual approach procedures.
  • Utility nonprecision instrument approachA runway built for propeller aircraft not exceeding 12,500 pounds gross weight. Runway has an instrument approach procedure that uses air navigation facilities with horizontal guidance. The runway can also have area type navigation equipment with approved nonprecision instrument approach procedures.
  • Visual visual approachA runway that supports only visual approach procedures.
  • Nonprecision instrument greater visibilityA runway with a nonprecision instrument approach procedure that allows for landing in visibility conditions greater than 200 ft. decision height.
  • Nonprecision instrument approach low visibilityA runway with a nonprecision instrument approach procedure that allows for landing in low visibility conditions. Low visibility conditions include decision heights less than 200 ft.
  • Precision instrumentA runway that uses an Instrument Landing System (ILS) or a Precision Approach Radar (PAR) for approach procedures.
String
input_airport_elevation

The highest point on any runway in an airport. The Linear Unit parameter sets the units for reference elevation. The tool will automatically populate this value from a z value in your aeronautical database if you are using the 18b data model.

Double
input_ois_unit

The runway length linear unit of measurement.

  • FeetRunway length is in feet. This is the default.
  • MetersRunway length is in meters.
String
input_ois_slope

Angular unit of measurement for slope values.

  • Grade (%)Slope angle is expressed as a grade (inclination) in percent.
  • Angle (°)Slope angle is expressed in degrees.
  • Rise (X:1)Slope angle is expressed as X units of run per 1 vertical unit. This is the default.
Long
primary_surface

Toggles on/off generation of an imaginary surface longitudinally centered on a runway.

  • CREATE_PRIMARY_SURFACECreates a primary surface. This is the default.
  • NO_CREATE_PRIMARY_SURFACEDoes not create a primary surface.
Boolean
primary_surface_length

Primary surface length excluding the length of the runway.

Double
primary_surface_width

Primary surface width excluding the width of the runway.

Double
conical_surface

Toggle on/off generation of a conical surface extending outward and upward from the periphery of the horizontal surface.

  • CREATE_CONICAL_SURFACECreates a conical surface. This is the default.
  • NO_CREATE_CONICAL_SURFACEDoes not create a conical surface.
Boolean
conical_surface_slope

The slope of the conical surface. Slope measurement units are specified in the conical_surface_slope parameter. The default value is 20 (20:1)

Double
conical_surface_offset

The length of the conical surface. Length measurement units are specified in the input_ois_unit parameter. The default value is 4000 feet.

Double
horizontal_surface

Toggle on/off generation of the horizontal surface. This surface lies above the established airport elevation. The surface is defined by lines tangent to arcs at horizontal_surface_radius distance from the center of each end of the primary surface.

  • CREATE_HORIZONTAL_SURFACECreates a horizontal surface. This is the default.
  • NO_CREATE_HORIZONTAL_SURFACEDoes not create a horizontal surface.
Boolean
horizontal_surface_radius
Double
horizontal_surface_height

The height of the horizontal surface above the established airport elevation. The default is 150 feet.

Double
approach_surface

Toggle on/off approach surface generation. The approach surface extends outward and upward from each end of the primary surface.

  • CREATE_APPROACH_SURFACECreates an approach surface. This is the default.
  • NO_CREATE_APPROACH_SURFACEDoes not create an approach surface.
Boolean
approach_surface_extendedwidth

The width of the approach surface outer edge.

Double
first_section_length

The length of the first section of the approach surface.

Double
first_section_slope

The slope of the first section of the approach surface.

Double
second_section_length

The length of the second section of the approach surface.

Double
second_section_slope

The slope of the second section of the approach surface.

Double
transitional_surface

Toggle on/off transitional surface generation. The transitional surface extends upward and outward from the primary and approach surfaces. This surface ends where it intersects the horizontal surface.

  • CREATE_TRANSITIONAL_SURFACECreates a transitional surface. This is the default.
  • NO_CREATE_TRANSITIONAL_SURFACEDoes not create a transitional surface.
Boolean
transition_surface_slope

The slope of the transitional surface. The default is 7 (7:1).

Double
output_feature_class

The output feature class that will contain the generated obstacle identification surfaces.

Feature Layer

Code Sample

FAAFAR77 example (Python window)

The following Python window script shows an example of the FAAFAR77 function.

# Input Runway Feature Class - change this path
infc = r'Database Servers\your_server_SQLEXPRESS.gds\ASP_PD (VERSION:dbo.DEFAULT)\ASP_PD.DBO.ADHPSurfaceLine' 

# Output Feature Class - this feature class must exist
outfc = "C:\\data\\work.gdb\\ObstacleArea_FAAFar77"

# Import the toolbox - verify this path exists
arcpy.ImportToolbox(r'C:\Program Files\ArcGIS\Desktop10.0\ArcToolbox\Toolboxes\Aeronautical Tools.tbx')

# exec FAA FAR 77
arcpy.FAAFAR77_Aeronautical(infc,"Objectid in (2)","0","Utility visual approach",2,"Feet","Rise (X:1)","CREATE_PRIMARY_SURFACE","200", "250","CREATE_CONICAL_SURFACE","20","4000","CREATE_HORIZONTAL_SURFACE","5000", "150","CREATE_APPROACH_SURFACE","100","1000","1","200","2","NO_CREATE_TRANSITIONAL_SURFACE","0",outfc)

Environments

This tool does not use any geoprocessing environments

Related Topics

Licensing Information

ArcView: No
ArcEditor: No
ArcInfo: Requires Aeronautical Solution

11/3/2011