Can someone explain the following:
Thanks.
Our GTX330 is connected to the 430W. What does this actually give us or give ATC?
It gives you ability to use a single altitude source for both units (less wiring generally). It enables auto GND/ALT switching
I understand we need to have a 330ES to get ADS-B in?
Some transponders do have ADS-B out capability. Your GTX might have this if it has ES. Then others might see some flight parameters, suchs as position, speed, heading, and depending on configuration some information on your flight plan. You need other means (a seperate receiver) for ADS-B in, so you could plot this data from other aircraft which have ADS-B.
How do I tell if the GTX330 we have has the ES modification?
If it shows GTX-330 it won’t, it shows GTX-330ES on start up it has.
If not, how can it be modified to give ES capability? Is it a software upgrade or new Txpdr?
It can be upgraded, it is an expensive hardware mod. Depending on your modifications you might want to choose another transponder which support ADS-B as a standard (suchs as Trig TT-31).
Is ADS-B in use in the EU. I presume many aircraft are fitted with ADS-B these days?
Airliners do have ADS-B. On general aviation aircraft this is just getting started. As the GTX-330ES is almost twice the price of the GTX-330, most choose for GTX-330 or GTX-328. The GTX-328 is not be able to modify.
believe the 330 outputs the call sign and aircraft type, as in the past I have been Identified directly after the initial call. Is this correct?
It outputs the call sign and the 24 bit ICAO technicall adress. From this information the aircraf type could be looked up in a database. It does not actually transmit the exact aircraft type. However it does transmit some data, such as maximum cruise speed. Such that an ATC controller can see which kind of aircraft you are and what your abilities are.
It gives you ability to use a single altitude source for both units (less wiring generally). It enables auto GND/ALT switching
Presumably, Jesse, you mean the GTX330’s pressure altitude goes to the GNS430 via ARINC429 (2 wires plus shield) rather than via Gray code (10 wires plus shield).
The GND/AIR auto switching would use data from the GNS430 to the GTX330 (RS232 or ARINC429). Does this feature actually work? It doesn’t work KLN94-GTX330 even though that is shown in the GTX330 IM.
This can also be done using a differential pressure switch. That’s how I had it done.
Is there any indication of ADS-B being relevant to light GA in Europe, ever, realistically? I have heard of 2020 which I think was in the USA.
A normal GTX330 has config (hold down some buttons during power-up – it’s in the IM) for the aircraft reg, the 24-bit Mode S code, and the airspeed.
Yes, that is correct, I don’t like that option to much, as the transponder fail will lead to a less acurate GPS as well, so I normally wouldn’t wire it like that. With the GTN no longer accepting gray code, one must use this approach for GTN.
Yes that ground flight function works fine. Be sure to have the correct settings at both the KLN94 and GTX. Some GPS have only valid output after selecting after giving a navigation input (direct to, waypoint or flight plane). Stupid.
I think ADS-B will be the future. It will give much better resolution and more information to ATC, both in the air and on the ground. Apart from that it could be a huge improvement for those who want accurate traffic alerts (by using ADS-B in as well). ADS-B is much less complex in hardware and software then having a active TAS system, and thus less expensive, and less power consumption while giving far more accurate information.
When I upgraded the avionics in my Katmai in 2010, the guys in Denver who did the upgrade offered me a GTX330ES (extended squitter) for $1500 more than the standard 330 so I bought it. At the time Canada, Australia and other were starting to use ADS-B in anger and the market for my aircraft is Canada hence fitting the ES unit.
In its standard form some data is transmitted on the 1090 frequency, I believe it’s registration, mode S code and flight level. To get the full ADS-B suite of data transmitted there has to be an RS232 (I think) connection made between one of the two GNS430W’s in my plane and software upgrades.
Last week RGV did the Far checks and I got them to fit the connection between the #2 430W and the GTX330ES. The 430w’s have two output settings, ADS-B and ADS-B+. I’m trying to find out the difference. On the ADS-B setting it seems the transponder is broadcasting tail number, flight level, ground speed, heading, rate of climb/descent and more. The 430W has to be Software version 5.1 and the transponder version 7.02. Both these software updates come with new AFMS document which in the case of the 430w upgrade gives me amongst other things an approval for P-RNAV (not an operational approval as that is an LoA from the FAA (my aircraft is N reg). The transponder software upgrade comes with another new AFSM document allowing ADS-B out. Again, this is not an operational approval as that is again an LoA from the FAA.
My pal has the Flightradar24 App, as I have. You’ll need the £1.99 pro version to get all the data. He picked up my ADS-B transmissions as I took off from Gloucester and followed me all the way back home. Everything was shown. It’s quite spooky really but the added advantage is my wife now has the app so she knows when to put the kettle on.
The only way to tell if the ADS-B is working is when the NO ADSB message goes out on the transponder when you take off.
To upgrade a 330 or 33 costs about $1200 but you must make sure your system can make use of it. The G1000 in the PA46 can’t so even if you get the upgrade it won’t output more than the current mode S. Mode S can however broadcast much more than you think such as selected altitude.
The 430w’s have two output settings, ADS-B and ADS-B+. I’m trying to find out the difference.
With ADS-B it is less accurate then with ADS-B+. With ADS-B+ setting it meets the accuracy and integrity specified by AC20-165A. The Garmin STC’s require certain setting witch MUST be used. (ADS-B+) I recommend you to leave the settings as set by the installer.
ADS-B is absolutely brilliant technology and it enables absolutely brilliant, accurate and vastly cheaper TCAS technology.
Airliners all radiate ADS-B – well except where somebody has turned off the transponder…
My queries above were concerned with practical usefulness in Europe.
ATC mostly can’t see it and if they can it doesn’t give them more than seeing your Mode S (tail number, 24-bit code, max speed, and if you have turned on Mode C they get the pressure altitude too) so I can’t see what extra service they can give you.
There is no TCAS system that can use it – AFAIK. My TAS605 system is supposedly ADS-B compatible, with some software upgrade, but a lot of things from Avidyne are vapourware. And I can see Mode C targets well enough – the problem is that at low level most people don’t fly with Mode C (or they don’t turn it on) and the same people are not going to be installing ADS-B, given that it is 100% sure to be exempted for UK VFR (to avoid another civil war).
Thanks all….Interesting stuff.
My queries above were concerned with practical usefulness in Europe.
On a long and boring flight, my ADS-B display allows me to spot all airliners around. Contrary to what is often written here, I manage to spot about 80% of what shows up on my traffic monitor, Mode C and ADS-B. Less than 80% when in IMC though 
