MODE S AND 8.33 RADIO

[howell]

We have been looking around to see who uses the 8.33 spacing, so far none found.
Question 1
Why have we to spend vast amounts of money on new radio equipment.
What happened to Mode S after all the initial trumpets.
Question 2
Why do we all have to spend more vast amounts of money on Mode S Transponders.
All comments welcome.
Chris Howell.

[howell]

Would some kind person let me know which LAA Magazine had the 8.33 write up and same with Mode S Please.

[John Price]

Chris,

In very simple terms.

Q1. By now SES ,Single European Sky, should have been up and running. This would have reduced frequency congestion, the overiding problem, by the allocation of frequencies by a central European Agency. However no country wanted to give up Sovereignty of it skies so all of them dragged there feet so badly that virtually nothing has happened. EASA was left with the problem that the simplest way forwards was to introduce the carriage of 8.33khz equipment by end 2017. Virtually no exceptions. Since they were not footing the bill and it only adds about .00001p to the price of an airline ticket, and this was a one of cost. It became mandatory. GA was, as usual, left to fund the whole thing itself, for no benefit.

Q2. Mode S. The CAA went through 2 consultations over its bit of kit. The basic principle was that Europe was running out of codes. So along with all other Aviation Authorities the good old CAA tried to force it on everyone.
They managed to get there backsides kicked on the first consultation, and not really giving it any thought tried the same thing again only asking the questions in a different way. The result was the same, a complete loss of face and massive embarrassment. So much so that the Chief Exec. Andrew Haines publicly apologised. The end result was that the CAA has taken the stance to breed Mode S into aircraft by not approving any mode A or C new fitments.
The Dutch descoverd quite spectacularly what happens when you get to many Mode S replies on a nice fine day.
As yet most aviation authorities are waiting to see what everyone else is doing so in real terms nobody is doing anything, and the whole Mode S across Europe, and the free world, is confused.
Looking long term Mode S will happen as it's the working bit for ADS B. And most of the push seems to be in that direction.

If any one knows better please correct me.

John.

[tnowak]

Hi Chris,

The 8.33KHz radio article is in the May 2013 magazine, starting on page 30.

Tony

[howell]

Many Thanks Tony.

[hazelpilot]

Can anyone tell me if the 8.33 radio is simply a change to existing radio base carrier, or if it also involves a narrower bandwidth?. So far I have discovered that I would have to buy a document from the government for £150 to tell me what the law is. Essentially I want to know the spectral envelope for 8.33 voice transmission. If the TX bandwidth is not changed that much it might be very easy to upgrade 25KHz radios to 8.33KHz spacing. But so far the CAA are not/will not tell me who decides which radios pass the 8.33 test or what the test is.
-Hazel

[howell]

Interesting Hazel the plot thickens, hopefully there is a Wise Person at LAA who could answer your question.
Chris. G-SAGE

[Ian Melville]

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. However this is insufficient so it is now further split to 8.33 kHz. 8.33-kHz spacing increases the number of channels available from 760 (which is in it's self a doubling of the 50khz -360 Channels of the past) to a figure close to three times that.

Bit like kicking all the fat people off a packed tube train so you can get more skinny ones on

Hazel, don't understand why you need to spend £150 for any document related to aviation law?

[howell]

Thanks Ian,
Maybe the interesting question is WHO finds the spacing insufficient and WHY is GA put to all this grief and expense!!
Many of us could manage quite happily without talking to ATC on an expensive new radio !!
Chris G-SAGE

[Brian Hope]

Hi Hazel, I'm not a radio expert by any stretch of the imagination but I do not believe any of the current 25 kHz sets will be usable once 8.33 comes online from the end of 2017, and modification will not be feasibly possible.
Because CAA were concerned that many people would go non-radio after the change, particularly those with simple aircraft and microlights, they approved the use of the current 8.33 Icom handhelds for use in aircraft in UK airspace. That was a very sensible concession and for many is an affordable option; I'll leave it to your imagination what owners will do when they nip across the Channel and want to use the radio.
The BGA has reported that The CAA has agreed that a small number of 25kHz frequencies, including some gliding frequencies, will be retained for use under a temporary exemption. The detail has yet to be established. As we reported in the last newsletter, the CAA has submitted an EU funding application to support GA re-equipage with 8.33kHz radios. The funding application is for 20% of the 8.33 equipage costs per aircraft.
EU funding? Well it’s worth a try but I’m certainly not holding my breath. And is a temporary exemption of a small number of frequencies really that helpful in the real world? If you tend not to land other than at farm strips, don’t talk to anybody en route and never cross controlled airspace, maybe, but for most it isn’t really a very practical option. I suppose for gliders it might be something of a reprieve but many people seem to be adopting a wait and see attitude, which seems reasonably wise approach. However, ultimately I think we’ll end up having to bite the bullet and buy an 8.33 radio if we want to fly serious cross-country because I don’t see Europe changing its mind – and even if we do leave the EU it won’t make a halfpence of difference, we’ll still have to follow their lead.

[howell]

Thanks for your input Brian, might it be possible to publish a fresh article in the LAA Magazine when you consider it a good moment.
I have read the article in the 2013 LAA Magazine and maybe we could see some fresh input as its going to become a hot potato soon.
At some point a Renewal Permit will not be granted without the new radio, will the same apply to transponders?
Chris. G-SAGE

[mikehallam]

Sorry to be a pedant Brian et al,

Surely with 8.33 spacing that should mean every third frequency step hits a 25 one too.
So forgetting actual band width questions per frequency, an otherwise perfectly good 25 set could still handle 760/2=360 frequencies.

Not all nonsense if one mostly in this bleak future would go non-radio or simply force more uses for SafetyCom.
E.g. Farnborough's watching service has no safety value unless you forgot something,. Shoreham & Goodwood are advisory only etc. So I suspect there'll either be silence or a whole load of light end fliers continuing with their old sets long beyond any EASA diktat !!

mike hallam.

[Chris Martyr]

I can see that this is going to turn into [yet another] Euro-Fiasco !

its going to become a hot potato soon.Chris. G-SAGE

If anything , it's turning into a bit of a cooling down potato , unless anyone's planning to be doing any flying above FL.195....

I do not believe any of the current 25 kHz sets will be usable once 8.33 comes online from the end of 2017

Surely, they'll be as usable on 01/01/18 as they were on 31/12/17 won't they ?
Let's not forget that the airlines have been using 8.33KHz bandwidth radios for ages and have been utilising 8.33KHz bandwidth frequencies for ages as well. The only thing that is going to change between now and 01/01/18 is that it will then become compulsory for all a/c EQUIPPED with radios [ and therein lies a grey area the size of London] that utilise the 8.33KHz bandwidth.
Handheld radios are not a part of an aircraft's Home Office regulated equipment and makes the users of them effectively NORDO's . I'm not for a second implying that handheld users should operate outside the law , but how on earth can they realistically keep any sort of tabs on this , apart from only allowing the sale of 8.33KHz handhelds after 01/01/18 , which is pretty much the way it is now anyway.
Obviously, any aircraft which is fitted with a 25KHz VHF set after Jan 2018 won't get past the PtF renewal stage , but the radio set will still perform as it has done in previous years.
People seem to be under the impression that any transmissions after Jan'18 will be unreadable if made on a 25KHz set, but they won't be any more unreadable than today.
The only change will be the legislation.....Euro-Babble....Which we all know, is unreadable ! [ ]

[Brian Hope]

Of course the radio will transmit and receive but it is likely interfere with the other two 8.33 frequencies within its 25 kHz bandwidth. That isn't going to be too much of an issue at first but as more 8.33 frequencies are allocated it will become more of an issue. That's why they are stopping the use of the 25 kHz sets.They are going to allow the use of 121.5 on the old sets apparently, no doubt by not allocating the 8.33 frequencies close to it.
As I said, I am not a radio expert but those that are tell me that interference from the broader channel spacing of current sets is the problem when 8.33 comes in.
Chris, as of the regulations currently extant or proposed, not having an 8.33 radio after December 2017 will not affect you getting you permit; nor will not having Mode S. The CAA tried their hand at imposing Mode S and failed and many people are still using Mode A/C or nothing at all.
Rgds, Brian.

[Chris Martyr]

I really can't take issue with any of that Brian. In theory that is .
Realistically though, none of this should affect G/A flyers. I still can't help comparing our situation with that of our brothers in the U.S. It does seem very ,very odd that they seem to carry on with their far more concentrated activities using 25KHz bandwidth spacing , mode C and,,, [probably the most relevant] their use of several different Unicom/SafetyCom frequencies. The logic of which probably results in other frequencies being freed up for the use of towered airfields.
The possibility of airfields in this country having similar, interfering frequencies is really quite miniscule and it is quite feasible that many airfields both here and in Europe may be allocated the same frequency and have no consequence whatsoever.
It's a pity really that we have to be chewing this over as I'm sure that we all agree with each other on the matter.
EuroControl,,,,,,,??? Didn't a previous generation fight in a world war against this sort of thing .