Peter wrote:
I don’t think ADS-B OUT emits any of that data.You can achieve a certified ADS-B OUT installation with a GTX335 etc etc fed from a standalone WAAS GPS (e.g. a GTX345 ) which has no connection to any of your avionics.
The stuff with the autopilot preset altitude etc is radiated via Enhanced Mode S, which AFAIK is not mandatory below 5700kg/250kt TAS/18 seats.
ADS-B can radiate a lot of the same data as Mode S enhanced surveillance. It usually doesn’t in basic installations but it is designed such that aircraft could have ADS-B and no Mode S. When you are in Germany or the UK and the controller calls you out for a wrong selected altitude, that is currently based on Mode-S.
People often confuse (because it is using the same initials) 1090 extended squitter (ADS-B out) and Mode-S Enhanced Surveillance (which just downlinks more aircraft data in a normal mode-S interrogation).
Surely, in Europe, it is not possible to have certified ADS-B OUT without going via a Mode S box?
And you can’t radiate what is not connected up to the other avionics.
My original Q was really whether ATC made any use of ADS-B and if so, what do they do, and what is the presentation they see?
This NATS blog post discuss Aberdeen using ADS-B for the helos over the North Sea. Of course much PR and not a lot of technical details.
The last pictures appears to show that a combined display is used by the ATCO.
Interesting. I wonder why NATS do this PR. They have a monopoly of all this stuff in a given area so don’t need to impress anyone 
I think that if ATC use ADS-B at all, that will need total data fusion. They don’t want to see more junk on their screens.
This is not difficult; see previous threads about merging Mode S and ADS-B aircraft, on GA TAS systems. The 24 bit ID is available in both packets so merging them is straightforward.
Peter wrote:
They have a monopoly of all this stuff in a given area so don’t need to impress anyone
They have the monopole for “en-route” and London Terminal control. All the airport are free to choose who they use for aerodrome/Tower and all but London ones are free to choose who do Radar/approach.
Likewise I’m sure there are loads of consultants including ANSP subsidiaries willing to help you (at cost) to setup a mixed radar/ADS-B system for your airport.
Doesn’t sound like ATC in Europe is using ADS-B…
Why would ATC use ADS-B in the first place where we have good SSR coverage (over western Europe) ?
There might be places where SSR coverage is poor but it is usually remote and with little air traffic.
Above north atlantic it would make sense although low-end GA is not directly concerned.
That’s a very interesting post, Guillaume, and thank you. So it sounds like France is not implementing it.
Does the UK have a specific problem which needs it?
There is a huge amount of hype going around on ADS-B and one would think “everybody” is getting into it.
If ATC weren’t going to use ADS-B data, then the mandate of June 2020 for aircraft over 250kts/5700 Kg would a waste of time.
Incidentally, what regulation is forcing airliners to radiate ADS-B? They have all (?) been doing it for years.
I don’t think it is the 250kt/5700kg one because some twin turboprops which are over 5700kg don’t have ADS-B.
