# 4.9. Taxonomy version number and name

<span lang="EN-GB">The Custom Taxonomy version and name is built as follows: </span>

<span lang="EN-GB" style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; color: #1b3891; mso-themecolor: text1; mso-fareast-language: ES;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';"> </span></span></span><span lang="EN-GB" style="mso-fareast-language: ES;">‘ECCAIRS Aviation’ string concatenated with:</span>

<span lang="EN-GB" style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; color: #1b3891; mso-themecolor: text1; mso-fareast-language: ES;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';"> </span></span></span><span lang="EN-GB" style="mso-fareast-language: ES;">Authority code - taken from the </span><span lang="EN-GB">A</span><span lang="EN-GB" style="mso-fareast-language: ES;">uthority details, followed by an underscore. </span><span lang="EN-GB">i</span><span lang="EN-GB" style="mso-fareast-language: ES;">.</span><span lang="EN-GB">e</span><span lang="EN-GB" style="mso-fareast-language: ES;">. </span><span lang="EN-GB">BE</span><span lang="EN-GB" style="mso-fareast-language: ES;">\_</span>

<span lang="EN-GB" style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; color: #1b3891; mso-themecolor: text1; mso-fareast-language: ES;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';"> </span></span></span><span lang="EN-GB" style="mso-fareast-language: ES;">Four-digit version code, which shows the </span><span lang="EN-GB">Central Taxonom</span><span lang="EN-GB" style="mso-fareast-language: ES;">y version on which the </span><span lang="EN-GB">C</span><span lang="EN-GB" style="mso-fareast-language: ES;">ustom is based. </span><span lang="EN-GB">i</span><span lang="EN-GB" style="mso-fareast-language: ES;">.</span><span lang="EN-GB">e</span><span lang="EN-GB" style="mso-fareast-language: ES;">. </span><span lang="EN-GB">8</span><span lang="EN-GB" style="mso-fareast-language: ES;">.</span><span lang="EN-GB">0</span><span lang="EN-GB" style="mso-fareast-language: ES;">.3.</span><span lang="EN-GB">1</span>

<span lang="EN-GB" style="font-family: Symbol; mso-fareast-font-family: Symbol; mso-bidi-font-family: Symbol; color: #1b3891; mso-themecolor: text1; mso-fareast-language: ES;"><span style="mso-list: Ignore;">·<span style="font: 7.0pt 'Times New Roman';"> </span></span></span><span lang="EN-GB" style="mso-fareast-language: ES;">Custom version number, in parenthesis. E.g. (C1)</span>

[![image.png](https://help.ci-aviationreporting.eu/uploads/images/gallery/2025-11/scaled-1680-/OJqimage.png)](https://help.ci-aviationreporting.eu/uploads/images/gallery/2025-11/OJqimage.png)