Airplane is ADS-B Out, but not seeing all the traffic

Fearless Tower

Fearless Tower

Touchdown! Greaser!
Joined
Jan 1, 2010
Messages
16,541
Location
Norfolk, VA
Display Name
Display name:
Fearless Tower
My Beech 18 is now ADS-B compliant. Equipped with GTX-330ES and GNS 530W. I’m using ForeFlight and a Stratus 2S for ADS-B in.

Since completing the ADS-B out, Ive noticed I’m only seeing maybe 10% more traffic on ForeFlight than I was prior. And and a lot of traffic that ATC is seeing near me is not showing up.

My ADS-B out appears to be working and was recently tested and my track shows up on FlightAware whenever I fly even without talking to ATC.

Sometimes I’ll see TIS traffic on my 530 that won’t show on ForeFlight. Sometimes I won’t see anything, but ATC will advise of traffic near me.

Anyone else experience similar? Is this the situation normal for ADS-B, or is this an issue within ForeFlight or the Stratus unit?
 
Is your transponder configured to tell the ground station that you have an ADS-B receiver on board?
 
It should be, but the setting can get missed if the shop doesn't know you have a portable receiver. The default is no ADS-B receiver installed.

Also, if you have a dual band receiver, the transponder should be set to tell the ground station you have both receivers on board . This lets the ground station know that it can suppress the ADS-R broadcasts as you are capable of receiving the ADS-B squitters directly air - to - air. The ground station will still broadcast the TIS-B data; typically on the 978 MHm link.
 
A benefit of panel fixed ADS-B in/out is your plane, and planes around you, can interrogate each other directly. I noticed more traffic with my GTX-345 than with just Stratus 2s.
 
@Axtel4 is right, if your transmission doesn’t say you have a receiver the ground filtering doesn’t create the “hockey puck” of airspace around your aircraft that traffic inside that airspace will be transmitted. If you’re not inside someone else’s “hockey puck” the ground won’t send up anything your receiver can use for traffic around your aircraft.

The transmission from your transponder also needs to tell the ground if you’re receiving on 978 UAT or 1090, so you’ll have to know what your portable receiver listens to.
 
Axtel4 said:
It should be, but the setting can get missed if the shop doesn't know you have a portable receiver. The default is no ADS-B receiver installed.

Also, if you have a dual band receiver, the transponder should be set to tell the ground station you have both receivers on board . This lets the ground station know that it can suppress the ADS-R broadcasts as you are capable of receiving the ADS-B squitters directly air - to - air. The ground station will still broadcast the TIS-B data; typically on the 978 MHm link.
Click to expand...
This makes sense. The airplane came with the 530W and a 330 (non-ES).

I upgraded the 330 to ES and all the Avionics shop did to make me ADS-B compliant was run the wire from the 530W to the 330.

So how do you adjust the internal settings on the 330? Is that something I can do?
 
There is one wire needed for GPS integrity source.
Your transponder is capable of ADS-B OUT only. There should be a configuration setting to allow the ground transmitter to provide TIS-B and FIS-B data to you as a client but you need a receiver to display it.

Your GNS 530W will display TIS-A traffic but that is not ADS-B and very limited info.

your Stratus 2S should be seeing everything TIS-B is sending you. There may be filters you can select to limit display of traffic. Check your setup.
 
You must log in or register to reply here.
Back
Top