---
title: "SERA.13001 Operation of an SSR transponder — ANNEX: Rules of the Air, SERA · Avioverse"
description: "When an aircraft carries a serviceable SSR transponder, the pilot shall operate the transponder at all times during flight, regardless of whether the…"
url: "https://avioverse.aero/regulations/easa/sera/annex-rules-of-the-air/section-13/sera-13001"
---

# SERA.13001 Operation of an SSR transponder

ANNEX: Rules of the Air · Regulation (EU) No 923/2012 · EAR revision 26 Aug 2025

IR Implementing rule

## SERA.13001 Operation of an SSR transponder

(a) When an [aircraft](https://avioverse.aero/glossary/easa/aircraft) carries a serviceable SSR transponder, the pilot shall operate the transponder at all times during flight, regardless of whether the aircraft is within or outside airspace where SSR is used for ATS purposes.

(b) Pilots shall not operate the IDENT feature unless requested by ATS.

(c) Except for flight in airspace designated by the [competent authority](https://avioverse.aero/glossary/easa/competent-authority) for mandatory operation of transponder, aircraft without sufficient electrical power supply are exempted from the requirement to operate the transponder at all times.

IR · SERA.13001 — Regulation (EU) No 923/2012 · Regulation (EU) 2016/1185 · SERA Easy Access Rules · EAR revision 26 Aug 2025

GM Guidance material

## GM1 SERA.13001 Operation of an SSR transponder

Pilots of [aircraft](https://avioverse.aero/glossary/easa/aircraft) engaged in formation join-ups are expected to continue operating the transponder until established in formation. Once established in formation, all except the lead aircraft should be instructed to ‘squawk standby’.

GM · GM1 SERA.13001 — Regulation (EU) No 923/2012 · ED Decision 2016/023/R · SERA Easy Access Rules · EAR revision 26 Aug 2025

GM Guidance material

## GM1 SERA.13001(c) Operation of an SSR transponder

Pilots of non-powered [aircraft](https://avioverse.aero/glossary/easa/aircraft) are also encouraged to operate the transponder during flight outside airspace where carriage and operation of SSR transponder is mandatory.

GM · GM1 SERA.13001(c) — Regulation (EU) No 923/2012 · ED Decision 2016/023/R · SERA Easy Access Rules · EAR revision 26 Aug 2025

GM Guidance material

## GM2 SERA.13001(c) Operation of an SSR transponder

[AIRCRAFT](https://avioverse.aero/glossary/easa/aircraft) WITHOUT SUFFICIENT ELECTRICAL POWER

This exemption addresses aircraft (e.g. sailplanes) that have electrical power supply only for the operation of on-board equipment, supporting notably communication, navigation and surveillance, which is not sufficient for the permanent operation of the SSR transponder.

Aircraft whose engines are electrically powered are not subject to this exemption since their certification provides for sufficient electrical power supply to cover both aircraft propulsion and other on-board supporting systems.

GM · GM2 SERA.13001(c) — Regulation (EU) No 923/2012 · ED Decision 2025/012/R · SERA Easy Access Rules · EAR revision 26 Aug 2025

[All rules in SECTION 13 SSR Transponder and ADS-B transmitters](https://avioverse.aero/regulations/easa/sera/annex-rules-of-the-air/section-13)

Consolidated from the EASA Easy Access Rules (revision 26 Aug 2025, 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.