The change to the minimal metadata requirements

Title

Change Proposal

Justification

Status

Notes

1

Update definition

Update Definitions page to include the different types of data sets. This can be a note in the ICAO data set entry.

A data set outlined in ICAO Annex 15.

Note: The different forms of ICAO data sets are listed in ICAO Annex 15 5.3.1.1:

a) AIP data set;
b) terrain data sets;
c) obstacle data sets;
d) aerodrome mapping data sets; and
e) instrument flight procedure data sets.

The obstacle data set has different requirements from the others so needs to be defined on its own.

Open

The different metadata requirements can be found at Basic properties for obstacles.

2

Change wording of DS-META-007 - Geographical extent of the data set on Metadata Requirements

Reword the requirement into two clauses:

Each ICAO obstacle data set shall be provided together with metadata giving the geographical extent of the data set.

Each ICAO data set, other than obstacle data sets, should be provided together with metadata giving the geographical extent of the data set.

The new wording will be reflected on Requirement 7_ Geographical extent of the data set.

The obstacle data set makes "Area of coverage" mandatory.

The tidy up of the table will ensure it is inline with the requirement/recommendation.

Open

3

Change the list of geographical elements to include.

The introduction on Requirement 7_ Geographical extent of the data set should become:

This requirement is fulfilled by including a geographic description (GeographicDescription) as a clear, textual description of the data set's geographical extent.

The inclusion of a bounding box (GeographicBoundingBox) or a polygon (BoundingPolygon) is a good practice in the GIS world. They are useful for applications that represent the data graphically, to set the initial window size. They are also facilitate the evaluation of the geographical coverage of a data set without having to parse and decode the full data set.

The Obligation / Condition row in tables should become:

Mandatory for obstacle data sets. Optional for other ICAO data sets. If provided:

GeographicDescription is mandatory.
Either GeographicBoundingBox or BoundingPolygon is recommended.

Reflects decision to concentrate on the provision of GeographicalDescription but allow the provision of other elements if available.

Open

4

New requirement for obstacle data sets covering integrity.

Add definition to Definitions:

Data integrity (assurance level). A degree of assurance that an aeronautical data and its value has not been lost or altered since the origination or authorized amendment. (ICAO Annex 15)

Add new requirement to Minimal Metadata Requirements:

Each ICAO obstacle data set shall be provided together with metadata giving the data integrity assurance level of the data set.

Add dedicated page with guidance.

tbd

Update Appendix B_ Complete Informative Example to reflect the guidance.

See Basic properties for obstacles.

Open

Are the levels:

critical
essential
routine?

What figure is expected in the metadata e.g.

a figure between 0.00 and 1.00 as per ED-119/DO-291?
or a reflection of the levels

See notes below. Decision was to use lineage and the levels (critical, essential, routine) to fulfill the requirement. Obstacle data is routine so that is used in the guidance.

5

Rename Requirement 7_ Geographical extent of the data set, etc.

The page name should be updated to e.g. DS-META-007 - Geographical extent of the data set.

This change should be applied to all the individual requirements pages.

The word "requirement" can be misleading. It is better simply to use the identifier.

Open

6

Update Appendix A_ Requirements Analysis to reflect final version of Annex 15 and PANS-AIM

Check the paragraph numbers used. Add the obstacle data set metadata requirements. Updated numbers should be reflected on Minimal Metadata Requirements as well.

Mostly tidy up.

Open

7

Update trace for Requirement 7_ Geographical extent of the data set on the Metadata Requirements page.

The requirement is traceable to PANS-AIM Table A6-2. Obstacle attributes for the obstacle data sets

The obstacle data set makes "Area of coverage" mandatory.

Open

8

Update guidance on

Requirement 3_ Validity of the data set

Update guidance to clarify what is meant by validity in this case. See comments on the page...

Open

Notes on data integrity discussions

The group considered various inputs for the data integrity discussion.

ED-98C/DO-276C:

Integrity
Definition: Integrity of data is the degree of assurance that the data and its value have not been lost nor altered since the data origination or authorized amendment.
Data Capture Rule: The integrity of the data set shall be expressed, indicating the probability of any single data element having been changed inadvertently since the creation of the data set [OBST-R034].
NOTE: For more information on integrity, refer to EUROCAE ED-76A / RTCA DO-200B.

ED-119C/DO-291C:

Integrity of data in the aeronautical data processing chain from data origination process to present data manipulation process.
Encoding: expressed in terms of probability of data loss or alteration (0=perfect, 1=all lost).
Example: essential ICAO Annex 15 0.0001=10e-5.

Also: AMDB section of ED-119C/DO-291C mentions integrity as an extension to ISO 19115. It has the following example: <amdb:dataIntegrity>0.00000001</amdb:dataIntegrity>

Discussions (16 July)

The group decided not to use ISO's extension mechanism.

The group point out that it is not recommended to use numerical values, because the ICAO SARPS do no longer use such numerical values. It requires just that the process ensures the 3 levels (routine, etc.)

It was therefore decided to use the Lineage option.