IntroductionFor Airport/Heliport, PANS-AIM requires some basic properties as part of the minimum AIP data set. These are
ICAO location indicator, name, designator IATA, served city, certified ICAO, certification date, certification expiration date, control type, field elevation, reference temperature, magnetic variation, reference point
The diagram below shows the AIXM classes, including the relevant data types, needed to encode that information:
Designator & Name
In AIXM 5, three attributes may be used to define the designator of an AirportHeliport:
A coding rule (see below) describes how the designator attribute shall be coded.
The locationIndicatorICAO is the International Civil Aviation Organization (ICAO) location indicator of the airport/heliport, as listed in ICAO DOC 7910.
The designatorIATA is the identifier that is assigned to a location in accordance with rules (resolution 763) governed by the International Air Transport Association (IATA).
The name attribute shall carry the primary official name of an airport/heliport as designated by an appropriate authority. The name attribute can take as a maximum 60 characters.
The servedCity property identifies the cities that the airport serves. In general, an airport may only serve one city. However, AIXM 5 provides the possibility to encode more than one.
The City class has a name attribute that is used to code the name of the city or town the airport/heliport is serving.
Several attributes are used to code information about the certification of the airport heliport.
certifiedICAO is used to indicating that the airport/heliport is certified per International Civil Aviation Organization (ICAO) rules.
The certificationDate is the calendar date when the airport/heliport certification has been issued by the supervising authority.
The certificationExpirationDate is the calendar date when the airport/heliport certification will become invalid.
Certificate is perpetual
In case that the certificate does not have an end of validity i.e. the certificate is perpetual:
- the certificationDate should be coded as appropriate and
- the certificationExpirationDate should be left empty with a nilReason equal-to ''inapplicable''.
The primary organisation type in terms of civil or military, which controls the airport/heliport is encoded by the controlType attribute.
The information of a civil or military airport is useful for charting purposes.
Some airports are uncontrolled, meaning that there is neither a civil nor a military air traffic control service provided.
In case of an uncontrolled airport there are two options:
- the controlType attribute should be left empty and a nilReason equal-to 'inapplicable' should be provided, or
- if you think that the first option is not explicit enough, use controlType equal-to 'OTHER:UNCONTROLLED'
The fieldElevation attribute is used to code the vertical distance above Mean Sea Level (MSL) of the highest point of the landing area. The corresponding accuracy value is given by fieldElevationAccuracy attribute.
The value for the field elevation is limited to 8 characters plus or minus before the decimal point and 4 characters after it.
Only numerical values shall be used for coding the field elevation value, i.e. 'GND', 'UNL', 'FLOOR' and 'CEILING' shall not be used (see also rule below).
As unit of measurement for the vertical distance only Feet ('FT') or Meters ('M') shall be used, i.e. Flight level ('FL') or Standards meters ('SM') shall not be used (see also rule below).
AIXM 5.1(.1) issue_018_Field elevation - Geoid Undulation
Where appropriate, PANS-AIM requires the geoid undulation to be provided for the point where the field elevation is measured.
In AIXM 5.1.(1) the geoidUndulation can only be provided for the ARP (i.e ElevatedPoint), which may not be the highest point of the landing area.
Workaround for AIXM 5.1(.1): An annotation for the property fieldElevation of the AirportHeliport may be used to encode that information including the accuracy of the Geoid Undulation.
Status AIXM 5.1: See CCB AIXM-122
The referenceTemperature attribute is used to code the monthly mean of the daily maximum temperatures for the hottest month of the year at an airport/heliport.
The unit of measurement for temperature may be coded as Degrees Celsius ('C') or Degrees Fahrenheit ('F') or Degrees Kelvin ('K').
The magnetic variation is the angular difference between Magnetic North and Geographical North (True north) measured at a given position and date.
Several attributes are used to provide information about the magnetic variation of an airport/heliport.
The magneticVariation attribute is used to provide the angular value of the magnetic variation. The value range allowed by AIXM is between -180 and 180 degrees.
A positive value indicates that Magnetic North is East of Geographical North.
A negative value indicates that Magnetic North is West of Geographical North.
The dateMagneticVariation is the year on which an associated magnetic variation was measured at the airport/heliport.
The magneticVariationChange is the annual rate of change of the magnetic variation at a specified airport/heliport.
In addition, PANS-AIM requires the accuracy to be provided. In AIXM the magneticVariationAccuracy attribute is used for that purpose.
Airport Reference Point
The ARP property identifies the Airport Reference Point. It is encoded by using the Point class. The elevation for an ARP is not required. For details about the encoding of Points see the topic Geometry.
In addition, PANS-AIM requires the accuracy to be provided. In AIXM the AirportHeliport.ARP.ElevatedPoint.horizonalAccuracy attribute is used for that purpose.
In an AIP, the site ( i.e. the location) of the reference point on the aerodrome and the direction and distance from the served city is published. Also PANS-AIM Appendix 1 (Aeronautical Data Catalogue) requires this information. In AIXM 5 these data can only be encoded as an annotation to the ARP property of AirportHeliport feature.
The figure below shows a simple example of the airport with the ICAO location indicator "EADD", which is also used as the designator of the airport.
The airport name is "DONLON/Intl.".
It serves the city of "Donlon".
EADD has a defined Airport Reference Point.
The magnetic variation at the airport was measured "1990" with "3 degrees West" and is since then "decreasing 0.03 degrees".
The field elevation is "30 Meters" and the corresponding reference temperature is "21 degrees Celsius".
The "Civil Aviation Administration" operates the airport.
The figure below shows the encoding of this information in AIXM 5.1:
Additional coding examples can be found in the AIP Data Set - Specimen (DONLON):
|AHP-EX-01||Airport basic data||//aixm:AirportHeliportTimeSlice [@gml:id ='AHP_EADD']|
|AHP-EX-01||Heliport basic data||//aixm:AirportHeliportTimeSlice [@gml:id ='AHP_EADH']|