Aeronautical Information Service
P.O. Box 75200
1117 ZT Schiphol
The Netherlands
Tel:+31 (0)20 406 3520

Aeronautical Information Circular



Publication date 07 MAY 2020


1 Introduction

The purpose of this AIC is to introduce the frequency monitoring code (FMC), also known as "listening squawk". A FMC is a transponder code that is to be selected by a VFR pilot as soon as the pilot is maintaining a listening watch on the corresponding communication channel.

FMC in the airspace around EHAM and EHRD will be implemented with effect from 18 JUN 2020. Pilots are urged not to activate a FMC on their transponder before this date, because this might cause immediate unwanted effects on the radar screens of radar units.

2 FMC to reduce effects of airspace infringements

FMC is part of an action plan initiated by LVNL, CLSK, KNVvL, AOPA and NACA to reduce the rising number of airspace infringements and their effects. It will initially be implemented for a limited number of COM channels in those areas where the traffic density and corresponding risk of airspace infringements requires 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 air traffic control (ATC) are to directly address the pilot and assist them in navigating out of the area. This can only be achieved when ATC knows on which COM channel the pilot can be contacted. A large number of pilots already request flight information service (FIS) when flying in class G or E, and maintain two-way radio communication. However, a significant number of pilots do not request FIS and fly without two-way radio communication in uncontrolled airspace. Even though this is allowed, uncertainty remains concerning which COM channel these pilots can be contacted on whenever an airspace is infringed.

The use of the FMC will significantly increase the ability of radar units to directly assist pilots when an airspace is infringed, thus reducing the effects of an infringement. The FMC is displayed to radar units on the radar screen. This makes it possible to directly address a pilot on the monitored COM channel, without multiple calls on several COM channels by different units.

3 Use of the FMC

COM channelATS unitFMC / transponder codeRelevant areas
124.300Amsterdam FIC7020Below Schiphol TMA 1
Below Schiphol CTR 2 and 3
Below Rotterdam TMA 1 and 2
122.990Rotterdam APP7010In Rotterdam TMA 1 and 2

Pilots that are flying in or in the vicinity of the relevant areas above, and are not receiving flight information service or air traffic control service, are strongly advised to monitor the relevant COM channel. After the COM channel has been selected, the pilot should select the corresponding FMC on the transponder.

When the pilot intends to switch back to a non-monitoring COM channel, the transponder is to be set to 7000 and thereafter the desired COM channel can be selected on the radio.

Note that the use of the FMC does not mean an implicit request for flight information service, such as traffic information. Flight information service shall only be available after requesting this through two-way radio communication.

4 VFR-flights receiving ATC or FIS

An FMC is only to be used when a pilot is flying without maintaining two-way radio communication with an ATS unit. Whenever a pilot requests FIS in class G or E or an ATC service in class C or D, and maintains two-way radio communication, the FMC shall not be selected. Instead, the transponder code shall remain 7000.

5 Further developments

The implementation of the FMC for the COM channels of Amsterdam Information and Rotterdam Approach will be evaluated throughout the year. If the use of the FMC successfully mitigates the effects of airspace infringements, the use will be expanded to other COM channels and areas in the Amsterdam FIR.

ISSN: 1386-6605