1  — Introduction

The purpose of this AIC is to introduce the Frequency Monitoring Code (FMC), also known as “listening squawk”. FMC is a Mode S transponder code that is to be selected by VFR pilots maintaining a listening watch on the corresponding COM channel.

The FMC will be implemented in the Belgian class G airspace with effect from 07 SEP 2023. Pilots are urged not to activate the FMC on their transponder before this date, as this might cause unwanted effects on the radar screens of ATS units.

The FMC is only to be used by pilots not maintaining a two-way radio communication with an ATS unit. Whenever a pilot requests FIS or receives ATC, the FMC shall not be selected. Instead, the transponder code shall remain 2000.

2  — Purpose of the FMC

The FMC is part of an action plan aiming to reduce the rising number of airspace infringements and their effects. It will initially be implemented for FIS channels where the frequency occupation time, the traffic density and corresponding risk of airspace infringements requites immediate measures.

It remains the sole responsibility of the pilot to avoid infringing an airspace without a proper clearance. However, when an airspace infringement does occur, without the use of FMC the main means of mitigating risk by ATC are to directly address the pilot and assist him in navigating out of the area. This can only be achieved when ATC knows on which COM channel the pilot can be contacted.

Many pilots already request FIS when flying in class G and maintain two-way radio communication. However, a significant number of pilots don’t request FIS and fly without two-way radio communication in uncontrolled airspace. Even though this is allowed, uncertainty remains concerning the COM channel on which these pilots can be contacted in case an airspace is infringed.

The use of the FMC will significantly increase the ability of ATS units to directly assist pilots when an airspace is infringed, thus reducing the effects of an infringement. The FMC is displayed to ATS units on the radar screen. This makes it possible to directly address a pilot on the monitored COM channel, avoiding the need for multiple calls on several COM channels by different units

3  — Use of the FMC

Pilots who are flying in Belgian class G airspace, and who are not receiving FIS or ATC, are strongly advised to monitor the COM channel of Brussels FIC. After the COM channel has been selected, the pilot should select the FMC if the aircraft is equipped with a Mode S transponder.

Pilots receiving FIS or ATC shall not select the FMC, the use of the transponder codes 2000 and 7000 remains unchanged.

Note that the use of the FMC does not mean an implicit request for FIS.

FIS will only be available after explicit request through two-way radio communication.