Starting Jan. 1, 2018, aircraft will need communications systems that have 8.33-kHz voice-channel spacing capability otherwise they might not be able to operate in any EU member states’ controlled airspace. Eurocontrol says extending 8.33 kHz below FL195 down to ground level is important, and that the 8.33-kHz requirement for higher altitudes in controlled airspace has been in effect for some time. Should the shortage of com frequencies not be addressed there will be potential for more air traffic delays; and it will be harder to implement safety improvements, according to Eurocontrol.

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