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Connecticut Airports Master Polygon

Frequently-asked questions:


What does this data set describe?

Title:
Connecticut Airports Master Polygon

Abstract:
Airports Polygon is a 1:24,000-scale, feature-based layer that includes all airport features depicted on all of the U.S. Geological Survey (USGS) 7.5 minute topographic quadrangle maps that cover the State of Connecticut and are listed on the Federal Aviation Administration (FAA) "Airport Data (5010) & Contact Information" June 5, 2008 report.  Airports in New York, Massachusetts and Rhode Island that are near the Connecticut state boundary are included. Airports that are listed by FAA and are visible on aerial photography (Connecticut 2004 Orthophotos and Connecticut 2006 NAIP Color Orthophotos from National Agriculture Imagery Program) are included. Airports that are listed by FAA but are not visible on aerial photography are not included. All airports listed by FAA are included in a separate point feature-based layer, Airport FAA CT. The airport point locations were generated from latitude and longitude coordinates contained in the FAA report and all the attribute information in the report was included. The airport layer is based partly on information from USGS topographic quadrangle maps published between 1969 and 1984 which does not represent airports in Connecticut at any one particular point in time. The layer does depict current conditions as to airports listed by FAA and having location identification codes and visible on aerial photography of 2004 and 2006. The layer delineates airports and heliports. It includes airport name, airport location code, type of facility, public or private use of facility and state the airport is located in. It does not include airport elevation, flight schedule, runway capacity, or ownership information. Features are polygonal and generally depict landing strips and perimeters for large and small airports and helicopter landing pads. Attribute information allows to cartographic representation (symbolize) and labeling of these features on a map. This layer was originally published in 1994 and slightly updated in 2005.

Supplemental information:
In 2004, the State of Connecticut Department of Environmental Protection developed automated procedures to systematically maintain feature topology and attribute integrity for a set of related transportation data produced by the agency during the 1980's and 1980's from the 1:24,000-scale USGS DLGs. These layers include Roads and Trails Master, Roads and Trails, Railroads Master, Railroads, Buffered Roads Master, Buffered Roads, Airports Master, and Airports. Automated procedures were developed using ArcInfo Workstation 8.3 software and the Arc Macro Language (AML) as a scripting environment and recorded in an AML file named MAKECOVER.AML for the transportation category of data for the State of Connecticut, Department of Environmental Protection. For additional information related to the original source of data from the U.S. Geological Survey, refer to the Data User Guides and Standards for 1:24,000-Scale Digital Line Graphs and Quadrangle Maps available from the U.S. Geological Survey, National Mapping Program.

  1. How should this data set be cited?

    State of Connecticut, Department of Environmental Protection (data editor and publisher), U.S. Geological Survey, National Mapping Program (data compiler), Federal Aviation Administration, Office of Aeronautical Information Services (data compiler), 20081707, Connecticut Airports Master Polygon: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA.

    Online links:
    Other citation details:
    The USGS is a collector of the data (compiler). The FAA is a collector of the data (compiler). The State of Connecticut, Department of Environmental Protection is the creator and maintainer of the data layer (editor) and producer (publisher) of this information for use. The 2008 Edition includes those geographic features published in 1994 that are relavant today. However, the 2008 Edition differs from information published in 1994 and 2005 as a result of corrections and improvements to feature geometry and feature attribute information. Previously undetected errors have been corrected. Feature attribute information (data fields) have been modified and new ones added. Except for periodic corrections, this layer includes information that is relatively static and does not change over time. Data compiled at 1:24,000 scale.

  2. What geographic area does the data set cover?

    Bounding coordinates:
    West: -73.733353
    East: -71.775151
    North: 42.108009
    South: 41.041178

  3. What does it look like?

    http://www.cteco.uconn.edu/metadata/dep/browsegraphic/airportsmasterpolyfullview.gif (GIF)
    Full View of Connecticut Airports Master Polygon. These data include some nearby airports in Massachusetts, New York and Rhode Island published on the USGS 7.5 minute topographic maps that cover Connecticut.

    http://www.cteco.uconn.edu/metadata/dep/browsegraphic/airportsmasterpolydetailview.gif (GIF)
    Detail view of Connecticut Airports Master Polyon features with airport names labeled with brown text.

  4. Does the data set describe conditions during a particular time period?

    Currentness reference:
    publication date

  5. What is the general form of this data set?

    Geospatial data presentation form: vector digital data

  6. How does the data set represent geographic features?

    1. How are geographic features stored in the data set?

      Indirect spatial reference:
      State of Connecticut, United States of America

      This is a Vector data set. It contains the following vector data types (SDTS terminology):
      • G-polygon (96)

    2. What coordinate system is used to represent geographic features?

      The map projection used is Lambert Conformal Conic.

      Projection parameters:
      Lambert Conformal Conic
      Standard parallel: 41.200000
      Standard parallel: 41.866667
      Longitude of central meridian: -72.750000
      Latitude of projection origin: 40.833333
      False easting: 999999.999996
      False northing: 499999.999998

      Planar coordinates are encoded using coordinate pair.
      Abscissae (x-coordinates) are specified to the nearest 0.000250.
      Ordinates (y-coordinates) are specified to the nearest 0.000250.
      Planar coordinates are specified in survey feet.

      The horizontal datum used is North American Datum of 1983.
      The ellipsoid used is Geodetic Reference System 80.
      The semi-major axis of the ellipsoid used is 6378137.000000.
      The flattening of the ellipsoid used is 1/298.257222.

      Vertical coordinate system definition:
      Altitude system definition:
      Altitude resolution: 1.000000
      Altitude encoding method: Explicit elevation coordinate included with horizontal coordinates

  7. How does the data set describe geographic features?

    Connecticut Airport Master Polygon
    Airports and heliports as polygon features (Source: State of Connecticut, Department of Environmental Protection and U.S. Geological Survey, National Mapping Program)

    OBJECTID
    Internal feature number. (Source: ESRI)
                      

    Sequential unique whole numbers that are automatically generated.

    NAME
    Official facility name. (ex. Chicago O'Hare Intl) (Source: Federal Aviation Administration)
                      

    Unique name text.

    SHAPE
    Feature geometry. (Source: ESRI)
                      

    Coordinates defining the features.

    AV_LEGEND
    ArcView Legend. Text field for symbolizing airport feature types on a map. Landing facility type. (ex. Airport, Balloonport, Seaplane Base, Gliderport, Heliport, Stolport, Ultralight)  (Source: State of Connecticut, Department of Environmental Protection and FAA)
                      

    ValueDefinition
    Airport
    [not provided]
    Heliport
    [not provided]

    LOCATIONID
    Location identifier unique 3-4 character alphanumeric identifier assigned to the landing facility. (ex. 'ORD' for Chicago O'Hare) (Source: Federal Aviation Administration)
                      

    Unique location id text.

    STATE
    State postal abbreviation (Source: State of Connecticut, Department of Environmental Protection)
                      

    USE_
    SHAPE.area
    SHAPE.len
    Entity and attribute overview:
    Includes polygonal airport features such as airports and heliports published on the U.S. Geological Survey 7.5 minute topographic quadrangle maps, listed by Federal Aviation Administration and visible on aerial photography . Information encoded about features includes airport feature type classification, a standard symbology classification scheme, airport location code, airport name, airport use and state.

    Entity and attribute detail citation:
    For additional information related to the original source of data from the U.S. Geological Survey, refer to the Data User Guides and Standards for 1:24,000-Scale Digital Line Graphs and Quadrangle Maps available from the U.S. Geological Survey, National Mapping Program. For additional information related to the FAA, refer to the "Airport Data (5010) & Contact Information" June 5, 2008 report or the Excel spreadsheet version, NfdcFacilities for CT. NFDC Airport Facilities Data Dictionary provides definition of the attributes in NfdcFacilities.
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Who produced the data set?

  1. Who are the originators of the data set? (may include formal authors, digital compilers, and editors)


  2. Who also contributed to the data set?

  3. To whom should users address questions about the data?

    Howie Sternberg
    State of Connecticut, Department of Environmental Protection
    79 Elm Street
    Hartford, Connecticut 06106-5127
    USA

    860-424-3540 (voice)
    860-424-4058 (FAX)
    dep.gisdata@ct.gov
    Hours of Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time
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Why was the data set created?

Airports Polygon is 1:24,000-scale base map data. It depicts the location of airports listed by FAA in June, 2008 and visible on aerial photography. For base map purposes, use this layer with other 1:24,000-scale base map data such as Hydrography Master, Roads and Trails Master, Railroads Master, and Towns Master. Not intended for maps printed at map scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet.). This layer is largely cartographic in nature and does  not include specific information about individual airports.

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How was the data set created?

  1. Where did the data come from?

    Source 1 - Airport_Master (source 1 of 6)

    State of Connecticut, Department of Environmental Protection (data editor and publisher), U.S. Geological Survey, National Mapping Program (data compiler), 19940101, Connecticut Airports Master: State of Connecticut, Department of Environmental Protection, Hartford, Connecticut, USA.

    Online links:
    Type of source media: disc
    Source scale denominator: 24000
    Source contribution:
    Airport features for all Connecticut quadrangle maps combined in a single, statewide layer. Airport_Master is in GeoDatabase Feature Class format.

    Source 2 - FAA Report (source 2 of 6)

    Federal Aviation Administration, Office of Aeronautical Information Services, 20080605, Airport Data (5010) & Contact Information formatted as Excel spreadsheet, NfdcFacilities.xls.

    Type of source media: online
    Source scale denominator: Not applicable
    Source contribution:
    A list of all FAA airport facilities in Connecticut and information about them such as facility name, facility identifier, type of facility, use of facility and latitude/longitude coordinates.

    Source 3 - Orthophoto 2004 (source 3 of 6)

    State of Connecticut, Departments of Environmental Protection, Public Safety, Transportation, 20040514, Connecticut 2004 Orthophoto.

    Type of source media: disc
    Source scale denominator: 12000
    Source contribution:
    Geographically rectified, digital photography of the State of Connecticut suitable for use in a geographic information system as a visual source of features in the landscape. Used for digitizing airport features.

    Source 4 - Orthophoto NAIP 2006 (source 4 of 6)

    USDA-FSA-APFO Aerial Photography Field Office, State of Connecticut, Department of Environmental Protection, 2007, Connecticut 2006 NAIP Color Orthophotography: USDA-FSA-APFO Aerial Photography Field Office, Salt Lake City, Utah.

    Type of source media: disc
    Source scale denominator: 40000
    Source contribution:
    Geographically rectified, digital photography of the State of Connecticut suitable for use in a geographic information system as a visual source of features in the landscape. Used for digitizing airport features.

    Source 5 - Airports_Polygon (source 5 of 6)

    State of Connecticut, Department of Environmental Protection, 20080717, Airports Polygon.

    Type of source media: disc
    Source scale denominator: 24000
    Source contribution:
    Updated airport polygon features for the State of Connecticut in GeoDatabase Feature Class format.

    Source 6 - Airports_FAA_CT (source 6 of 6)

    State of Connecticut, Department of Environmental Protection (data editor and publisher), 20080717, Airports FAA CT.

    Online links:
    Type of source media: disc
    Source scale denominator: 24000
    Source contribution:
    Updated airport point features for the State of Connecticut in GeoDatabase Feature Class format.

  2. What changes have been made?

    Date: 2008 (change 1 of 1)
    Person responsible for change:
    Diana Danenberg
    State of Connecticut, Department of Environmental Protection
    79 Elm Street
    Hartford, Connecticut 06106
    USA

    860-424-3540 (voice)

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How reliable are the data; what problems remain in the data set?

  1. How well have the observations been checked?

    All attributes have valid values. Values are within defined domains. The basis for all attribute fields except State is the FAA report spreadsheet, NfdcFacility.xls, for Connecticut facilities. The attribute accuracy of the FAA data is not known. These values were manually entered.

  2. How accurate are the geographic locations?

    This portions of this data that came from the 1994 (2005 edition) airport layer comply with United States National Map Accuracy Standards for 1:24,000 scale maps. According to this standard, not more than 10 percent of the points tested are to be in error by more than 1/50 inch (40 feet) measured on the publication scale of a USGS 7.5 minute topographic quadrangle map. The remaining was screen digitized and the positional accuracy is unknown.

  3. How accurate are the heights or depths?

  4. Where are the gaps in the data? What is missing?

    The layer is incomplete in the sense that it does not include features for all FAA listed airports, heliports and seaplane bases. It is complete in the sense that it includes all FAA listed airports and heliports for which a representation can be located on aerial photography as of 2006. This data is not updated.

  5. How consistent are the relationships among the observations, including topology?

    Polygon features conform to the following topological rules. Polygons are single part. There are no duplicate polygons. Polygons do not self overlap. Polygons do not overlap other polygons. Polygons are bound by lines. Line features conform to the following topological rules. Lines are single part. There are no duplicate lines. Lines do not self overlap. Lines do not overlap other lines. Lines intersect only at nodes, and nodes anchor the ends of all lines. Lines do not overshoot or undershoot other lines they are supposed to meet and intersect. The tests of logical consistency were not performed.

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How can someone get a copy of the data set?

Are there legal restrictions on access or use of the data?

Access constraints: None. The data is in the public domain and may be redistributed.
Use constraints:
No restrictions or legal prerequisites for using the data. The data is suitable for use at appropriate scale, and is not intended for maps printed at scales greater or more detailed than 1:24,000 scale (1 inch = 2,000 feet). Although this data set  has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata. When printing this data on a map or using it in a software application, analysis, or report, please acknowledge the State of Connecticut, Department of Environmental Protection, the U.S. Geological Survey, National Mapping Program and  the Federal Aviation Administration, Office of Aeronautical Information Services as the source for this information. For example, include the following data source description when printing this layer on a map: Airports - From the Airports Polygon layer, compiled and published by CT DEP, USGS and FAA. Source map scale is 1:24,000.

Distributor 1 of 1

  1. Who distributes the data set?

    State of Connecticut, Department of Enviromental Protection
    79 Elm Street
    Hartford, Connecticut 06106-5127
    USA

    860-424-3540 (voice)
    860-424-4058 (FAX)
    dep.gisdata@ct.gov
    Hours of Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time

  2. What's the catalog number I need to order this data set?

    Connecticut Airports Master Polygon

  3. What legal disclaimers am I supposed to read?

    Although this data set  has been used by the State of Connecticut, Department of Environmental Protection, no warranty, expressed or implied, is made by the State of Connecticut, Department of Environmental Protection as to the accuracy of the data and or related materials.  The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the State of Connecticut, Department of Environmental Protection in the use of these data or related materials. The user assumes the entire risk related to the use of these data. Once the data is distributed to the user, modifications made to the data by the user should be noted in the metadata.

  4. How can I download or order the data?

    • Availability in digital form:


    • Data format:
      in format Shapefile, Feature Class, Coverage (version ArcGIS) Size: 0.075
      Network links:http://www.ct.gov/deep

    • Cost to order the data: An online copy of the data may be accessed without charge.


  5. Is there some other way to get the data?

    The data distributor does not provide custom GIS analysis or mapping services. Data is available in a standard format and may be converted to other formats, projections, coordinate systems, or selected for specific geographic regions by the party receiving the data.

  6. What hardware or software do I need in order to use the data set?

    Geographic information sytem (GIS), computer-aided drawing or other mapping software is necessary to display, view and access the information.

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Who wrote the metadata?

Dates:
Last modified: 20111222

Metadata author:
Diana Danenberg
State of Connecticut, Department of Environmental Protection
79 Elm Street
Hartford, Connecticut 06106-5127
USA

860-424-3540 (voice)
860-424-4058 (FAX)
dep.gisdata@ct.gov
Hours of Service: Monday to Friday, 08:30 to 16:30 Eastern Standard Time

Metadata standard:
FGDC Content Standards for Digital Geospatial Metadata(FGDC-STD-001-1998)

Metadata extensions used:
  • http://www.esri.com/metadata/esriprof80.html

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