8.33-kHz Radio Channel Spacing Changes Are Coming to Europe

PT 3 M minute read
8.33-kHz Radio Channel Spacing Changes Are Coming to Europe

Europe is getting ready for the final phase in the deployment of 8.33-kHz radios – with mandatory use throughout European airspace by 2018. While this will solve long-standing radio frequency congestion problems, for at least a decade, it will put a burden on many business aircraft operators. All operators flying to Europe, or planning such operations in the future, need to be aware of the proposed phased implementation of 8.33-kHz channel spacing below FL195. Here’s an overview of what you should know:

1. What is 8.33 channel spacing?

Aircraft radio systems transmit on a Very High Frequency (VHF) band between 117.975 and 137 MHz. The number of available VHF assignments has increased over the years by splitting the radio spectrum into narrower bandwidths from 50-kHz to 25-kHz channels. The bandwidth can support 760 channels, if channels are spaced by 25 kHz. In 1994, it was decided to introduce a further channel split from 25 to 8.33 kHz. 8.33-kHz spacing was introduced above Flight Level (FL) 240 in International Civil Aviation Organization (ICAO) European (EUR) regions in October 1999 and above FL 195 from March 15, 2007. Currently, 8.33-kHz channels have been implemented in the airspace of all 20 ICAO EUR region states. So far, Europe is the only region that’s moved to 8.33-kHz channel spacing.

2. Why is 8.33-kHz channel spacing necessary?

Without the extension of 8.33-kHz channel spacing, it’s likely that only about 70% of future requirements for frequencies in Europe can be met. This lack of available frequencies would delay, or make impossible, airspace improvements to increase capacity. Simulations have shown that with the expected growth in traffic, the average level of delay caused by capacity shortfalls, throughout Europe in 2020, could be four times as high as current levels and seven times as high by 2025 if no action is taken. Although extension of 8.33-kHz channel spacing will not fully resolve all capacity problems, it will enable airspace re-structuring. This should reduce future delay costs between now and 2025 by over €3 billion (3.9 billion USD) in present value terms.

3. Who requires 8.33-kHz radios?

Any aircraft operating above FL195 within European airspace must be equipped with 8.33-kHz radios per European Commission (EC) Regulation No. 1265/2007 dated October 27, 2007. The first phase of the next change, to 8.33-kHz channel spacing below FL195, will be January 1, 2014. By this date, any general aviation (GA) aircraft operating instrument flight rules (IFR) must be equipped with 8.33 kHz-capable radios. By December 31, 2014, frequencies used by operations control (OPC) must be converted to 8.33-kHz channel spacing. By January 1, 2018, all aviation radios operating in ICAO EUR regions must have 8.33-kHz channel spacing capability. These regulations affect all Eurocontrol members, with the exception of Morocco.

4. Are waivers possible for ops without 8.33-kHz channel spacing?

Currently, if you don’t have 8.33-kHz channel spacing, you may operate below FL195 and have the option of requesting waivers to operate above FL195. Be aware, however, that waivers must be requested and approved by each country you’re transiting.

5. How much will these equipment upgrades cost?

These regulations add costs for Eurocontrol, while also adding cost to operators who need to upgrade to, or obtain, radios with 8.33-kHz channel spacing. Many operators have already upgraded their radios to 8.33-kHz channel spacing, and new aircraft are typically equipped with 8.33-kHz channel spacing. Anyone seeking to purchase an older aircraft – with plans to fly within European airspace – needs to consider the cost of required radio upgrades. The good news is that planned radio channel spacing changes should be sufficient to handle radio frequency requirements through 2030. Studies show that all anticipated demand can be met with the planned extension of 8.33 kHz below FL195. The costs of implementation, while substantial, are not unreasonable compared to benefits, which are possible.

6. Where can additional information be found?

a. The commission implementing Regulation (EU) 1079/2012 lays out 8.33-kHz requirements.
b. For more information on 8.33-kHz channel spacing requirements below FL195, see this link.


Operating within European airspace is already very restrictive for operators without 8.33-kHz radio spacing. With new regulations requiring 8.33-kHz channel spacing below FL195, all operators – who do not already have mandated radio frequency capabilities – will need to consider radio equipment upgrades in the near future.


If you have any questions about this article or flight planning in Europe, contact me at markmiller@univ-wea.com.

Got a question for Mark about this article?