[The Westmorland Flyer]

The real reason is that they hoped to force aeronautical users off part of the airband so that they could flog it off to broadcasters (as they did the "guard band", which required us to buy all-new ILS receivers to be "FM immune").

And, of course, the government requiring Ofcom (and CAA, come to that) to cover its costs and, in addition, raise tax revenue. It woz the other lot wot dun it but I note that the current incumbents show no signs of reversing the policy despite its obvious safety implications.

[kanga]

..
And, of course, the government requiring Ofcom (and CAA, come to that) to cover its costs and, in addition, raise tax revenue. It woz the other lot wot dun it ...

but it was the lot before that who established the principle (supported by legislation and regulation) that all regulatory 'trading agencies' of Government must cover their costs (and make a profit) by charging users for being regulated. Ofcom were merely (relatively) late in realising that they had control of a chargeable asset without any responsibility for the operational (including safety) aspects of that charging (because that was the CAA's business)..

[Paul_Sengupta]

Going back to the spectrum use stuff for a bit, would it not be better, if they were to try and implement 8.33kHz spacing, to split the band, so that perhaps the lower part retained 25kHz spacing, then you had an upper part split into 8.33kHz frequencies? Thus no interference and sideband issues.

[The Westmorland Flyer]

Going back to the spectrum use stuff for a bit, would it not be better, if they were to try and implement 8.33kHz spacing, to split the band, so that perhaps the lower part retained 25kHz spacing, then you had an upper part split into 8.33kHz frequencies? Thus no interference and sideband issues.

That's exactly what is done at the moment. In effect, the issue comes down to whether to retain this arrangement or to make the entire air band 8.33kHz spacing, with one or two notable exceptions such as 121.5MHz. If they retain the split then 25kHz radios will continue to work just fine in "their" spectrum and 8.33/25kHz radios (there are no 8.33kHz-only radios) will work across the entire air band.

[Robin500]

Is there any possibility, however remote, of getting the implementation of 8.33 watered down, or is it cast in stone for all airband users come 2018 ?

[The Westmorland Flyer]

Is there any possibility, however remote, of getting the implication of 8.33 watered down, or is it cast in stone for all airband users come 2018 ?

I guess that depends what you believe and who you believe in. The CAA directive makes it clear that it's cast in stone. But that's happened before only to have deadlines deferred or discarded.

Mode-S is the obvious case study. It brought a similar level of unwanted cost for no benefit to GA and in the end, for most of us, it just hasn't happened other than as part of the normal equipment life-cycle replacement. Part of the reason for that was the very slow roll-out of Mode-S capable ground equipment. Whether the same thing will happen with ground radio systems remains to be seen.

It would be relatively easy to "water down" the requirements so that 8.33kHz didn't affect the overwhelming majority of GA for the foreseeable future. It needs a more robust attitude on the part of the regulator to European directives that are not in the national interest. 8.33kHz could be a useful measure of the success of the new GA unit and the commitment to reduce red tape/gold plating.

[chevvron]

It would be relatively easy to "water down" the requirements so that 8.33kHz didn't affect the overwhelming majority of GA for the foreseeable future. It needs a more robust attitude on the part of the regulator to European directives that are not in the national interest. 8.33kHz could be a useful measure of the success of the new GA unit and the commitment to reduce red tape/gold plating.

It would reduce the impact on GA if airfields (say) situated in class G airspace were not allocated 8.33 frequencies and were not required to fit new equipment.
There are many VHF aeronautical band frequencies used for non ATC/AFIS/A/G activities eg Ops/company frequencies and MOD/contractors trials frequencies. 129.7 is a commonly used 'company' frequency and 130.5 is used as a 'trials' frequency (very rarely). If these operators were re-allocated 8.33 frequencies, (and they're the ones who can afford to change) it would make many more 25 khz frequencies available for GA use.

[The Westmorland Flyer]

It would reduce the impact on GA if airfields (say) situated in class G airspace were not allocated 8.33 frequencies and were not required to fit new equipment.
There are many VHF aeronautical band frequencies used for non ATC/AFIS/A/G activities eg Ops/company frequencies and MOD/contractors trials frequencies. 129.7 is a commonly used 'company' frequency and 130.5 is used as a 'trials' frequency (very rarely). If these operators were re-allocated 8.33 frequencies, (and they're the ones who can afford to change) it would make many more 25 khz frequencies available for GA use.

In principle what you suggest is reasonable. The perfect storm is created when spectrum pricing is added into the 8.33kHz mix. This uniquely UK tax heist will tend to encourage ground operators to go 8.33kHz if they can, as it reduces the annual licence costs dramatically. There is actually no need in the UK for any more channels (25kHz or 8.33kHz), for GA or, indeed virtually any other airband user. The entire 8.33kHz debacle is a classic European fudge, created by Europe to solve the problem of inefficient channel allocations on the continent.

[kanga]

..the problem of inefficient channel allocations on the continent.

.. which, in theory, the Single European Sky project ought to be able to help solve (as the single FAA, with comparable size and many more GA airfields, aircraft, and movements, does in the US ). The historic problem was, at least in part, down to the mutual independence of national CAAs and A/G Freq allocators. But I agree that the 'spectrum charging' (unique to UK, but a logical consequence of Treasury policies since early '80s of Regulator being required to (over)charge the Regulated in all fields) has aggravated things here

[The Westmorland Flyer]

.. which, in theory, the Single European Sky project ought to be able to help solve (as the single FAA, with comparable size and many more GA airfields, aircraft, and movements, does in the US ). The historic problem was, at least in part, down to the mutual independence of national CAAs and A/G Freq allocators

Absolutely. It is most odd that the SES project, which has been going for some years (though I think not as long as 8.33kHz) has not scuppered 8.33kHz altogether. But then perhaps it's not surprising - bureaucracies are experts in ensuring that their left and right hands have no idea what the other is up to. Why, after all, have one set of costly policies when you could have two?

[Keef]

No, it's not like that.

OfConn needs the 8.33/25 fiasco so that they can charge absurd licence fees for 25kHz channels, thus driving most A/G stations off the air. Then they can sell the frequencies to FM Broadcasters ... oh bother! The airband is covered by International Agreement and can't be sold off. Oh, in that case let's get rid of FM broadcast instead.

[The Westmorland Flyer]

Cynic! But you might have a point

[Keef]

Years of experience, TWF. I saw the first draft of the OfConn "Airband Spectrum Pricing" proposal. It was an excellent example of politically-inspired bureaucratic muddled-thinking, littered with non-sequiturs and errors. Lots of us produced detailed critiques of it. They reworked it to sanitise it (a bit) then published it again ... and again ... until they got one that they could get enacted. Frankly, I was appalled (not something I often am). It put a large price on safety. Sadly, I don't see any political group prepared to throw it (and its charges) where it should go.

[GrahamB]

All aircraft, that are equipped with radios, to be capable of 8.33 kHz channel spacing capability - 1 January 2018

The latest Clued Up misquotes this as 'All radios have to be 8.33Khz' or words to that effect, which is clearly not the same thing.

My Com1 is 8.33Khz. Com2 is not, but my SOP is to only use it for ATIS, so I'm reluctant to rip it out.

I'm going to try some airborne trials at some point to see how good the receive side filtering is - if I can continue to adequately pick up ATIS transmitted on an 8.33Khz channel, it's staying in the aircraft until it goes BER!

[riverrock]

Sorry Graham. It's the CAA that are wrong (I haven't looked at the IN).
See http://eur-lex.europa.eu/LexUriServ/Lex ... 024:EN:PDF

This Regulation shall apply to all radios operating in the
117,975-137 MHz band (‘the VHF band’) allocated to the aero­
nautical mobile route service, including systems, their consti­
tuents and associated procedures.

Unless the rules change - you'll need to change / bin your COM2.