EU Updates Lost Comms and Emergency Descent Rules

On May 1, the Standardised European Rules of the Air (SERA) were updated – bringing new procedures for lost comms, emergency descents, and even a brand-new transponder code.

SERA is essentially the rulebook that ensures consistent flight procedures across EU airspace. It’s developed by EASA and is legally binding for all EU member states.

Each country still publishes its own AIP, but when SERA is updated, it overrules anything outdated in those local documents. So even if a country’s AIP hasn’t caught up yet, you’re still expected to follow the new SERA rules!

You can download the updated SERA guidance here, but here’s a quick look at the main changes:

Radio Communication Failure Procedures

Lost comms? The new SERA rules introduce a second transponder code, and defines which one to use – depending on whether or not you’re diverting.

🟦 Squawk 7600 = Not diverting

Use 7600 if you’re flying under IFR and:

You’ve lost radio communication, and
You’re continuing with your IFR flight – even if you’re in VMC.

This means you’re sticking to the standard lost comms procedures: continue based on your last clearance, possibly to your destination or alternate, and let ATC protect that airspace.

One important change to be aware of when using the 7600 code: the old 7-minute rule in lost comms situations has been replaced. Under the updated rules, if you’re continuing under IFR after losing communications, you must now maintain your last assigned level and speed for 20 minutes (instead of 7) before taking further action under lost comms procedures. This extended buffer gives ATC more time to identify your position and protect your track.

🟩 Squawk 7601 = You ARE diverting

Use 7601 if:

You’re flying under IFR
You’ve lost comms
You’re in VMC, and
You decide to land at the nearest suitable airport instead of continuing the flight.

So 7601 is a brand-new code introduced to give ATC a clear picture of what you’re doing. Instead of guessing whether you’re continuing IFR or trying to land visually, ATC knows right away: you’re diverting to land, and they can adjust separation and support accordingly.

From the helpful PDF published by Skeyes (the Belgium air navigation service provider). Click to download.

Emergency Descent Procedure

This has been updated with clearer priorities! The procedure now starts with “Navigate as deemed appropriate by the pilot” – replacing the older instruction to always turn off route before beginning the descent. So the new rule gives the pilot full discretion to navigate as needed – possibly turning, possibly descending straight ahead.

There are also some changes to what ATC should do: broadcasting an emergency message now comes first (not just “if necessary”), and there’s clearer guidance to inform other ATS units (this wasn’t explicitly stated before).

Plus some guidance on what other aircraft should do if they hear the emergency descent broadcast: keep flying their current clearance, maintain listening watch, and watch for conflicting traffic visually and with ACAS. Pretty standard stuff, but this wasn’t explicitly mentioned in the previous guidance.

Notams and AIP Updates

One issue to be aware of here – most countries won’t update their AIPs until May 15 with the next AIRAC cycle. But these new SERA rules are legally binding from May 1 and take precedence over any outdated AIP content, so you must follow the updated SERA guidance!

So far, France appears to be the only country that has issued a Notam acknowledging/warning us about the changes:

LFFF F0627/25 (Issued for LFBB LFEE LFFF LFMM LFRR) - 
APPLICATION OF THE NEW EUROPEAN REGULATION IR SERA 2024/404 
IN FORCE ON MAY 1ST, 2025 WITH THE INTRODUCTION OF POINT SERA.14083 
RELATING TO PROCEDURES IN CASE OF RADIO COMMUNICATION FAILURE. 
MODIFICATION OF RADIO FAILURE PROCEDURE : INTRODUCTION OF THE NEW 
EMERGENCY CODE 7601 AND MODIFICATION OF THE 7-MINUTE RULE TO 20 MINUTES. 
REF AIP ENR1.1. 01 MAY 00:00 2025 UNTIL PERM. CREATED: 30 APR 10:03 2025

And another issue to be aware of – some non-EU countries in Europe are not updating their rules!

Switzerland have decided to confuse everyone by saying they won’t be implementing the 7601 code anytime soon:

LSAS A0252/25 - IFR FLT SHALL USE SSR CODE 7600 IN CASE OF RCF EVEN WHEN 
CONTINUING IN VMC TO THE NEAREST SUITABLE AD. SSR CODE 7601 AS DEFINED 
BY SERA.14083 NOT YET IMPLEMENTED. 15 MAY 00:00 2025 UNTIL 31 JAN 23:59 2026. 
CREATED: 02 MAY 10:01 2025

And the UK has published this doc saying that no changes are being made to the UK’s RCF procedures.

As the UK and Switzerland are not EU countries, they can do what they like. EU countries don’t have this option – they’re all legally required to apply new SERA rules on the effective date.

Bottom line: keep an eye out for more AIRAC/AIP updates and Notams from other European countries in the coming days as they clarify how they’re implementing the new SERA procedures!

EU Updates Lost Comms and Emergency Descent Rules