8.33 khz radios.
 

All civil aircraft and Aeronautical Radio Stations operating on the VHF aeronautical band are having to change their radios from those with a bandwidth conducive to 25 khz spaced frequencies to 8.33 khz bandwidth. Invariably this means throwing out a working radio and replacing it.
Just out of curiosity, is this happening to aircraft/ground stations with UHF aeronautical band radios too?

8.33 KHz channel spacing on air band VHF frequencies has been a requirement for some time in European airspace. Most UHF are either 50 KHz or 25 KHz, the latter being the latest requirement. I am not aware of any plans to change that.

The VHF Band 8.33 KHz Channel Spacing requirement first came into force in 1999 for the 30 European States in Eurocontrol, applicable to all aircraft operating above FL245. Just about every Public Transport Aircraft that operated routes within or across Europe was brought into compliance back then.

EASA brought the level down to FL 195 in 2007. The rule was further extended to ground level on 16 Nov.2012. All aircraft operating in European airspace must be equipped with VHF 8.33 KHz channel spacing from 01 January 2018. The rule applies to all State aircraft (i.e. Military), with exception granted only to those that will be withdrawn from service by 31 December 2025.

The rule doesn't apply to the UHF Band which is not used by civilian operators

Blacksheep - I'd say those dates were extended? I bought my first 8.33 radio for a helicopter in 1997. 13 years before, we were well into ASR889, which introduced 25kHz. Both were good opportunities for replacing obsolescent kit. A 50>25 modification was possible in most cases but, as they say, never modify a mod, and 25>8.33 was more demanding.

Indeed the 8.33 was coming in in 1997. Very slow knowledge spread in the military. In the FJ force only the F3 was to be modified as it had a need to operate above 245. The Muds, which did not routinely operate at higher levels were exempt.

And the start of channelisation - too long to easily remember and fit in the available spaces on the equipment - so what you hear and see isn't what you get.

8.33kHz channels & frequencies

Yes, they led and we got on the back of their production contract. They had multiple failures which delayed acceptance, but they were in a part of the spec we didn't need, so a suffix was added to the part number for rotary. That radio had 12.5, 8.33, 5, 2 and 1kHz spacing. I'd say 1997, perhaps 1998, was the first time we had one working on the rig. I know I wrote the system specs in December 1994.