EU Member States started to deploy 8.33 kHz channel spacing and starting January 1st 2018 833 will become a requirement for most aircraft. State (military) aircraft are usually exempt, at least for a grace period.
If your aircraft is equipped with 8.33 kHz capable radio equipment make sure you enter the 'Y' in item 10a of the flight plan form.
If your aircraft is not equipped with 8.33 kHz capable radio equipment but equipped with UHF radio enter the letter 'U' and 'Z' in item 10a of the flight plan form. In item 18 enter 'COM/EXM833'.
Most EU states have published information about the 833 introduction in an Aeronautical Information Circular (AIC). Please contact our NOTAM section in case you need further information from any of the EU countries.
Click here for:
Status of the 833 Voice Channel Spacing Implementation below FL195