wmo-im/iwxxm

Removal of IWXXM representations involving TAC element "Supplementary information/State of the runway"

Closed this issue · 4 comments

blchoy commented

Initial request

Amendment 79 to ICAO Annex 3 had removed the requirement to provide information on "State of the runway" in the TAC template of METAR/SPECI, which was in accordance to the planned applicable date (5 Nov 2020) of Amendment 77-B on "the use of a global reporting format for assessing and reporting runway surface condition":

Amendment 80 had delayed the application date of Amendment 77-B and the corresponding changes in the TAC template of METAR/SPECI in Amendment 79 to 4 Nov 2021:

Since producers do not need to use new IWXXM METAR/SPECI schemas to "not report" the state of the runway, removal of relevant elements in IWXXM METAR/SPECI has been deferred to the next significant change to IWXXM.

Amendment details

The change to IWXXM involves the removal of iwxxm:runwayState and associated XML elements.

Comments

Nil.

Requestor(s)

@blchoy on behalf of ICAO WG-MIE.

Stakeholder(s)

WMO TT-AvData and ICAO WG-MIE.

Publication(s)

Manual on Codes (WMO-No. 306), Volume I.3.

Expected impact of change

LOW

Collaborators

N/A.

References

Amendments 77-B, 79 and 80 to ICAO Annex 3.

Validation

N/A.

blchoy commented

One thing we need to remind ourselves is under this situation whether we want to advance the current version of METAR/SPECI (v3.1.0) to v3.1.1 or v.3.2.0. In accordance to our [https://github.com/wmo-im/iwxxm/wiki/Common-approaches-accross-exchange-models#version-policy Version Policy], this falls into minor change and so the version number should be advanced to v3.2.0.

blchoy commented

After checking the following will be removed:

UML model:

  1. Class AerodromeRunwayState
  2. Class RunwayDeposits
  3. Class RunwayContamination
  4. Class RunwayFrictionCoefficient

The revised context diagrams are as follow:

XML elements:

  1. iwxxm:runwayState
  2. iwxxm:AerodromeRunwayState
  3. iwxxm:RunwayDeposits
  4. iwxxm:RunwayContamination
  5. iwxxm:RunwayFrictionCoefficient

Schematron rules:

  1. METAR_SPECI.AerodromeRunwayState-1
  2. METAR_SPECI.AerodromeRunwayState-2
  3. METAR_SPECI.AerodromeRunwayState-3

Opportunity is taken to also remove the never used complexType "RunwayPropertyType" in common.xsd.

blchoy commented

Another thing we will need to handle: Whether we want to remove examples "metar-EDDF-runwaystate.xml" and "metar-LKKV.xml" (both contain information on runway state), or modify them to remove runway state information. My personal preference is to remove them as we have a suite of examples under iwxxm-translation repository and there is no point to have too many examples to go with the schemas.

Of course we can also consider to modify them and move them to the iwxxm-translation repository. But why border doing so as we already have great examples created by @mgoberfield ?

blchoy commented

Included in IWXXM 2025-2RC1.