---
title: "ATCO.C.040 Validity of synthetic training device instructor endorsement — ANNEX I – PART ATCO – REQUIREMENTS FOR THE LICENSING OF AIR TRAFFIC CONTROLLERS, ATCO · Avioverse"
description: "The STDI endorsement shall be valid for a period of three years."
url: "https://avioverse.aero/regulations/easa/atco/part-atco-requirements-for-the-licensing-of-air/subpart-c/atco-c-040"
---

# ATCO.C.040 Validity of synthetic training device instructor endorsement

ANNEX I – PART ATCO – REQUIREMENTS FOR THE LICENSING OF AIR TRAFFIC CONTROLLERS · Regulation (EU) 2015/340 · EAR revision 14 Jun 2024

IR Implementing rule

## ATCO.C.040 Validity of synthetic training device instructor endorsement

(a) The STDI endorsement shall be valid for a period of three years.

(b) The STDI endorsement may be revalidated by successfully completing refresher training on practical instructional skills and on current operational practices during its validity period.

(c) If the STDI endorsement has expired, it may be renewed by:

(1) receiving refresher training on practical instructional skills and on current operational practices; and

(2) successfully passing a practical instructor competence [assessment](https://avioverse.aero/glossary/easa/assessment);

within the year preceding the application for [renewal](https://avioverse.aero/glossary/easa/renewal).

(d) In the case of first issue and renewal the period of validity of the STDI endorsement shall start not later than 30 days from the date on which the assessment has been successfully completed.

\[applicable until 3 August 2024 - Regulation (EU) 2015/340]

(a) The STDI endorsement shall be valid for a period of 3 years.

(b) The STDI endorsement may be revalidated by successfully completing refresher training on practical instructional skills and on current operational practices during its validity period.

(c) If the STDI endorsement has expired, it may be renewed if, within the 12 months preceding the application for renewal, the STDI endorsement holder has:

(1) received refresher training on practical instructional skills and on current operational practices; and

(2) successfully passed a practical instructor competence assessment.

(d) In the case of first issue and renewal, the period of validity of the STDI endorsement shall start not later than 30 days from the date on which the assessment has been successfully completed.

\[applicable from 4 August 2024 - Implementing Regulation (EU) 2023/893]

IR · ATCO.C.040 — Regulation (EU) 2015/340 · Regulation (EU) 2023/893 · ATCO Easy Access Rules · EAR revision 14 Jun 2024

GM Guidance material

## GM1 ATCO.C.040(b) Validity of synthetic training device instructor endorsement

[REVALIDATION](https://avioverse.aero/glossary/easa/revalidation)

(a) Successful completion of the refresher training in practical instructional skills and current operational practices may be verified by several means, for example by:

(1) dedicated or continuous [assessment](https://avioverse.aero/glossary/easa/assessment);

(2) peer assessment; or

(3) demonstration of practical instructional skills.

(b) Current operational practices may be refreshed by transitional and pre-on-the-job training.

(c) The verification should be undertaken following the completion of the refresher training.

GM · GM1 ATCO.C.040(b) — Regulation (EU) 2015/340 · ED Decision 2015/010/R · ATCO Easy Access Rules · EAR revision 14 Jun 2024

[All rules in SUBPART C – REQUIREMENTS FOR INSTRUCTORS AND ASSESSORS](https://avioverse.aero/regulations/easa/atco/part-atco-requirements-for-the-licensing-of-air/subpart-c)

Consolidated from the EASA Easy Access Rules (revision 14 Jun 2024, extracted 13 Oct 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.