Exchange File Format


Table of Contents

 

1. Exchange File Overview

 

2. Record Format

2.1 Identification Code

2.1.1 General Data Category

2.1.2 General Data Record Type

2.1.2.1 Various Contents (000-299)

2.1.2.2 Reference System Definition Codes (300)

2.1.2.3 3D Positions (400)

2.1.2.4 Distance and Elevation (500)

2.1.2.5 Length and Width (600)

2.1.2.6 2D Positions (700)

2.1.2.7 Value (Distance, Width, etc.) (800)

2.1.2.8 Orthometric and Ellipsoidal Elevation (900)

2.2 Specific Data Records

2.2.1 Airport Specific Records

2.2.1.1 Airport Identification (A000)

2.2.1.2 Airport Name (A010)

2.2.1.3 Airport Jurisdiction (A020)

2.2.1.4 Airport Magnetic Declination (A030)

2.2.1.5 Airport Status (A040)

2.2.1.6 Datum Tie (A050)

2.2.1.7 Airport Elevation (A060)

2.2.1.8 Airport Reference System (A310)

2.2.1.9 Airport Location Point (A710)

2.2.1.10 Air Traffic Control Tower (A910)

2.2.2 Runway Specific Records

2.2.2.1 Runway Identification (R000)

2.2.2.2 Runway Width (R810)

2.2.2.3 Runway Type (R010)

2.2.2.4 Runway Flags (R02*)

2.2.2.5 Runway End Position (R40*)

2.2.2.6 Displaced Threshold - by position (R41*)

2.2.2.7 Displaced Threshold - by distance (R51*)

2.2.2.8 Stopway - by position (R72*)

2.2.2.9 Stopway - by length (R62*)

2.2.2.10 Blastpad - by position (R73*)

2.2.2.11 Blastpad - by distance (R63*)

2.2.2.12 Distance To Boundary - by position (R74*)

2.2.2.13 Distance To Boundary - by distance (R84*)

2.2.2.14 TDZE - output only (R92*)

2.2.2.15 Profile Point Status (R090)

2.2.2.16 Profile Point - by position (R490)

2.2.2.17 Profile Point - by distance (R590)

2.2.3 Feature Specific Records

2.2.3.1 Feature Identification (F000)

2.2.3.2 Feature Status Record (F010)

2.2.3.3 Feature Position (F410)

2.2.3.4 Base Elevation (F020)

2.2.3.5 Auxiliary Date (F030)

2.2.4 Miscellaneous Records

2.2.4.1 Chart Reference System (C310)

2.2.4.2 NGVD29 to NAVD88 Conversion Factor (C010)

 

3. Quick Reference Record Charts

Airport Records

A000 - Airport Identification Record

A010 - Airport Name

A020 - Airport Jurisdiction

A030 - Airport Magnetic Declination

A040 - Airport Status

A050 - Datum Tie

A060 - Airport Elevation

A310 - Airport Reference System

A710 - Airport Location Point

A910 - Air Traffic Control Tower

Runway Records

R000 - Runway Identification

R810 - Runway Width

R010 - Runway Type

R02* - Runway Flags

R40* - Runway End Position

R41* - Displaced Threshold - by position

R51* - Displaced Threshold - by distance

R72* - Stopway - by position

R62* - Stopway - by length

R73* - Blastpad - by position

R63* - Blastpad - by Distance

R74* - Distance to Boundary - by position

R84* - Distance to Boundary - by distance

R090 - Profile Point Status

R490 - Profile Point - by position

R590 - Profile Point - by distance

Runway Records

F000 - Feature Identification

F010 - Feature Status

F410 - Feature Position

F020 - Base Elevation

F030 - Auxiliary Date

Miscellaneous Records

C310 - Airport Reference System

C010 - NGVD29 to NAVD88 Conversion Factor

 

Appendix A. Special Codes

Existence Flags

Accuracy Codes

Horizontal Datum Tie Codes

Ellipsoidal Datum Tie Codes

Orthometric Datum Tie Code

Attribute Code 1

Attribute Code 2 (Control/Plotting Symbology)

Attribute Code 3 (Navigational Aids)

Attribute Code 4 (Not currently used)

Primary Condition Codes (refer to the ‘405' for specifics)

Secondary Condition Codes (refer to the ‘405' for specifics)



1. Exchange File Overview


The Exchange File Format is a users guide for preparing and submitting data for storage in the National Geodetic Survey Obstruction Chart Database (OCDB). It provides in detail the format and structure of every field allowable by the OCDB. Also included are dependencies, field widths, record order requirements and field choice lists.


For questions regarding the Exchange File Format please contact:


Michael Keltz

phone: (301) 713-1428 ext. 171

email: keltz@c0n06.ngs.noaa.gov


For errors or questions regarding this document please contact:


Frank Mowry

phone: (301) 713-3260 ext. 157

email: fmowry@ngs.noaa.gov


2. Record Format

 

The following sections describe all the possible records found in an Exchange File. These sections are broken down by record and then by field. Each field is further broken down by: description, position, range, format, and example. All records have the same basic structure. All records contain at most 112 characters. They consist of a variable number of fields. Each field has a corresponding existence code. The existence flags and their positions are defined in Appendix A. The field format contains a special symbol defined below.


                                           A                         Alphabetic capital or lowercase characters only (A-Z)

                                           9                          Numeric and sign only (0-9, +, -, .)

                                           X                         Alphanumeric, sign and decimal point


Note: All numeric values are in feet unless otherwise specified.


2.1 Identification Code


Each record begins with a four character identification code. This code is broken down into two parts, the single alpha character General Data Category and the three digit numeric General Data Record Type.



2.1.1 General Data Category


The first character in column 1 is the general data category. All records for a given data category must be provided before the next category begins. There are four valid data category codes:



                                           A                         Airport Data

                                           R                         Runway Data

                                           F                          Feature Data

                                           C                         Chart Information


Explanations of these categories will be given in further detail under the appropriate section for each category.


 

2.1.2 General Data Record Type


Characters 2-4 represent an integer value representing the data record for each category. If the first digit is a 3 through 9, the record is a standard series record. Otherwise it is a special format record. The following list contains the integer value range and the corresponding contents of the record:



                                           000-299               Various Contents

                                           300                      Reference System Definition Codes

                                           400                      3D Positions With Date And Source

                                           500                      Distance And Elevation With Date And Source

                                           600                      Length And Width With Date And Source

                                           700                      2D Positions Without Date And Source

                                           800                      Value (Distance, Width, etc.) With Date And Source 

                                           900                      Orthometric and Ellipsoidal Elevation With Date And Source


These data records are broken down into specific fields in sections 2.1.2.1 through 2.1.2.8.


2.1.2.1 Various Contents (000-299)


2.1.2.2 Reference System Definition Codes (300)


Field 1: Reference System Code

              Description: Reference system in which the positions are expressed

              Position: Columns 5-9

              Range: None, value is always 0 (zero)

              Format: 99999

              Example: 0


Field 2: Zone Code

              Description: Zone for the reference system

              Position: Columns 10-14

              Range: None, value is always 0 (zero)

              Format: 99999

              Example: 0


Field 3: Horizontal Unit Code

              Description: Units in which positions are expressed.

              Position: Columns 15-19

              Range: Currently only:

                            5            DMS (degrees, minutes, seconds)

              Note:     Additional codes will be added in the future only if modifications to the OC Database allow for

                            positions in units other than DMS.

              Format: 99999

              Example: 5


Field 4: Horizontal Datum Code

              Description: Year of datum in which positions are expressed

              Position: Columns 20-24

              Range: Year of Datum, 27 or 83

              Format: 99999

              Example: 27


Field 5: Vertical Unit Code

              Description: Units in which elevations and distances are expressed

              Position: Columns 25-29

              Range: Currently only:

                            1            feet

              Note:     Additional unit codes will be added at some point in the future only if modifications to the OC Database allow for elevations and distances in units other than feet

              Format: 99999

              Example: 1


Field 6: Vertical Datum Code

              Description: Year of datum in which elevations are expressed

              Position: Columns 30-34

              Range: Year of Datum, 29 or 88

              Format: 99999

              Example: 29


2.1.2.3 3D Positions (400)


Field 1: Longitude

              Description: Longitude where sign represents hemisphere

              Position: Columns 5-19

              Range: -1800000 to +1800000, values west represented as negative

              Format: DDDMMSS.SSSS where

                            -180 < DDD < + 180

                            0 <= MM <= 59

                            0 <= SS <= 59

              Example: -1235832.1281


Field 2: Latitude

              Description: Latitude where sign represents hemisphere

              Position: Columns 20-34

              Range: -900000 to +900000, values south represented as negative

              Format: DDMMSS.SSSS where

                             -90 < DD < +90

                            0 <= MM <= 59

                            0 <= SS <= 59

              Example: 245328.7315


Field 3: Elevation, Orthometric

              Description: Refer to the FAA NO. 405

              Position: Columns 35-49

              Range: None

              Format: 99999999999.999

              Example: 469.845


Field 4: Elevation, Ellipsoidal

              Description: Refer to the FAA NO. 405

              Position: Columns 50-64

              Range: None

              Format: 99999999999.999

              Example: 382.289

 

Field 5: Determined Date

              Description: Survey Date that data in this record was determined

              Position: Columns 66-76

              Range: None

              Format: dd-mmm-yyyy where

                            dd          - 2 character integer day

                            mmm     - First 3 alpha characters of the month

                            yyyy      - 4 character integer year

              Example: 18-DEC-1996




Field 6: Verified Date

              Description: Most recent Survey Date that data in this record was verified

              Position: Columns 78-88

              Range: None

              Format: dd-mmm-yyyy where

                            dd          - 2 character integer day

                            mmm     - First 3 alpha characters of the month

                            yyyy      - 4 character integer year

              Example: 18-DEC-1996


Field 7: Source Code, Position

              Description: Specifies the source of position

              Position: Column 90

              Range:   F - field

                            O - office

                            D - digitizer

                            A - analytical plotter

              Format: A

              Example: F


Field 8: Source Code, Elevation

              Description: Specifies the source of elevation

              Position: Column 92

              Range:   F - field

                            O - office

                            D - digitizer

                            A - analytical plotter

              Format: A

              Example: F


2.1.2.4 Distance and Elevation (500)


Field 1: Distance

              Description: Distance (real) from an endpoint

              Position: Columns 5-19

              Range: None

              Format: 99999999999.999

              Example: 72149.968


Field 2: Elevation, Orthometric

              Description: Refer to the FAA NO. 405

              Position: Columns 35-49

              Range: None

              Format: 99999999999.999

              Example: 12138.325




Field 3: Elevation, Ellipsoidal

              Description: Refer to the FAA NO. 405

              Position: Columns 50-64

              Range: None

              Format: 9999999999.9999

              Example: 14325.424


Field 4: Determined Date

              Description: Survey Date that data in this record was determined

              Position: Columns 66-76

              Range: None

              Format: dd-mmm-yyyy where

                            dd          - 2 character integer day

                            mmm     - First 3 alpha characters of the month

                            yyyy      - 4 character integer year

              Example: 18-DEC-1996


Field 5: Verified Date

              Description: Most recent Survey Date that data in this record was verified

              Position: Columns 78-88

              Range: None

              Format: dd-mmm-yyyy where

                            dd          - 2 character integer day

                            mmm     - First 3 alpha characters of the month

                            yyyy      - 4 character integer year

              Example: 18-DEC-1996


Field 6: Source Code, Distance

              Description: Specifies the source of distance

              Position: Column 90

              Range:   F - field

                            O - office

                            D - digitizer

                            A - analytical plotter

              Format: A

              Example: D


Field 7: Source Code, Elevation

              Description: Specifies the source of elevation

              Position: Column 92

              Range:   F - field

                            O - office

                            D - digitizer

                            A - analytical plotter

              Format: A

              Example: F




2.1.2.5 Length and Width (600)


Field 1: Distance

              Description: Distance (real) from runway endpoint

              Position: Columns 5-19

              Range: None

              Format: 99999999999.999

              Example: 1244.945


Field 2: Width

              Description: Width (real) of runway

              Position: Columns 20-34

              Range: None

              Format: 99999999999.999

              Example: 324.376


Field 3: Determined Date

              Description: Survey Date that data in this record was determined

              Position: Columns 66-76

              Range: None

              Format: dd-mmm-yyyy where

                            dd          - 2 character integer day

                            mmm     - First 3 alpha characters of the month

                            yyyy      - 4 character integer year

              Example: 18-DEC-1996


Field 4: Verified Date

              Description: Most recent Survey Date that data in this record was verified

              Position: Columns 78-88

              Range: None

              Format: dd-mmm-yyyy where

                            dd          - 2 character integer day

                            mmm     - First 3 alpha characters of the month

                            yyyy      - 4 character integer year

              Example: 18-DEC-1996


Field 5: Source Code, Distance

              Description: Specifies the source of distance

              Position: Column 90

              Range:   F - field

                            O - office

                            D - digitizer

                            A - analytical plotter

              Format: A

              Example: F

 



Field 6: Source Code, Elevation

              Description: Specifies the source of Elevation

              Position: Column 92

              Range:   F - field

                            O - office

                            D - digitizer

                            A - analytical plotter

              Format: A

              Example: F


2.1.2.6 2D Positions (700)


Field 1: Longitude

              Description: Longitude where sign represents hemisphere

              Position: Columns 5-19

              Range: -1800000 to +1800000, values west represented as negative

              Format: DDDMMSS.SSSS where

                             -180 < DDD < +180

                            0 <= MM <= 59

                            0 <= SS <= 59

              Example: -1751119.1281


Field 2: Latitude

              Description: Latitude where sign represents hemisphere

              Position: Columns 20-34

              Range: -900000 to +900000 values south represented as negative

              Format: DDMMSS.SSSS where

                             -90 < DD < +90

                            0 <= MM <= 59

                            0 <= SS <= 59

              Example: 245328.7315


2.1.2.7 Value (Distance, Width, etc.) (800)


Field 1: Value (Distance, etc.)

              Description: Distance, width or other miscellaneous real value

              Position: Columns 5-19

              Range: None

              Format: 9999999999.9999

              Example: 1231.4433


Field 2: Verified Date

              Description: Most recent Survey Date that data in this record was verified

              Position: Columns 78-88

              Range: None

              Format: dd-mmm-yyyy where

                            dd          - 2 character integer day

                            mmm     - First 3 alpha characters of the month

                            yyyy      - 4 character integer year

              Example: 18-DEC-1996


Field 3: Source Code, Value

              Description: Specifies the source of value

              Position: Column 90

              Range:   F - field

                            O - office

                            D - digitizer

                            A - analytical plotter

              Format: A

              Example: F


2.1.2.8 Orthometric and Ellipsoidal Elevation (900)


Field 1: Elevation, Orthometric

              Description: Refer to the FAA NO. 405

              Position: Columns 35-49

              Range: None

              Format: 99999999999.999

              Example: 13245.786


Field 2: Elevation, Ellipsoidal

              Description: Refer to the FAA NO. 405

              Position: Columns 50-64

              Range: None

              Format: 99999999999.999

              Example: 14456.556


Field 3: Verified Date

              Description: Most recent Survey Date that data in this record was verified

              Position: Columns 78-88

              Range: None

              Format: dd-mmm-yyyy where

                            dd          - 2 character integer day

                            mmm     - First 3 alpha characters of the month

                            yyyy      - 4 character integer year

              Example: 18-DEC-1996


Field 4: Source Code, Elevation

              Description: Specifies the source of Elevation

              Position: Column 92

              Range:   F - field

                            O - office

                            D - digitizer

                            A - analytical plotter

              Format: A

              Example: D





2.2 Specific Data Records


These records are specific to the three general data categories: Airport, Runway, and Feature. The first character represents which general category the record falls under. A - Airport, R - Runway, and F - Feature. Like the General Data Record Type, characters 2-4 represent an integer value representing the data record for each category. If the second character is a 3 through 9, the record is a standard series record.


2.2.1 Airport Specific Records


The following records contain information about the airport.


2.2.1.1 Airport Identification (A000)


Note: This is the only record which is absolutely required for the exchange file.


Field 1: OC Number

              Description: National Geodetic Survey tracking number

              Position: Columns 5-10

              Range: 1 to 99999

              Format: 999999

              Example: 4367

              Dependancy: This record or the Airport ID is required


Field 2: OC Edition

              Description: Most current

              Position: Columns 11-16

              Range: 1 to 99999

              Format: 999999

              Example: 6


Field 3: Airport ID

              Description: Airport Identifier (refer to FAA ORDER 7350.**, AS AMENDED)

              Position: Columns 18-21

              Range: None

              Format: AAAA

              Example: TWS

              Dependancy: This record or the OC Number is required


Field 4: Site ID

              Description: FAA Identification number

              Position: Columns 23-32

              Range: None

              Format: XXXXXXXXXX

              Example: 045O8.A


Field 5: Previous Airport ID

              Description: The previous Airport Identifier (if applicable)

              Position: Columns 34-37

              Range: None

              Format: AAAA

              Example: CNW


2.2.1.2 Airport Name (A010)


Field 1: Name

              Description: Name of Airport on Survey Date

              Position: Columns 6-75

              Range: None

              Format: (70)A

              Example: Baltimore Washington International Airport


Field 2: Verified Date

              Description: Most recent Survey Date that data in this record was verified

              Position: Columns 78-88

              Range: None

              Format: dd-mmm-yyyy where

                            dd          - 2 character integer day

                            mmm     - First 3 alpha characters of the month

                            yyyy      - 4 character integer year

              Example: 18-DEC-1996


2.2.1.3 Airport Jurisdiction (A020)


Field 1: City

              Description: Associated City

              Position: Columns 6-45

              Range: None