ADS-B effectiveness

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Rich
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ADS-B effectiveness

Post by Rich »

Given that I'm still seeing some interesting comments out on social media I put together this matrix of traffic detection scenarios based on the various combinations of ADS-B in/out for a mixed population we live with now and, well, indefinitely.
ADS-B Traffic matrix.pdf
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2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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CFIDave
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Re: ADS-B effectiveness

Post by CFIDave »

I've been flying around for 2.5 years in our DA62 with a GTX335R ADS-B OUT (only) transponder -- since the GTX345R *still* isn't certified for NXi DA62s!

My plane does have a TAS605 active traffic unit to display transponder-equipped traffic directly on the MFD and PFD. However, because I often fly in congested airspace around DC, I usually have a Stratus box and iPad running Foreflight mounted in the plane so I can also display ADS-B IN traffic.

I've been surprised by how often I pick up transponder-only targets via TAS on the MFD map, but never see those same airplanes show up on my iPad and Stratus box -- especially since I'm almost always within range of an ADS-R ground repeater when flying in the eastern US.

Since my plane is continually broadcasting ADS-B Out messages via its GTX335R transponder, ADS-B ground stations are supposed to send me ADS-B In traffic info for transponder-only aircraft. I should be "seeing" them via my iPad, but often don't.

Since my GTX335R is configured to broadcast that I don't have ADS-B IN installed (legally true, since there's nothing with ADS-B IN permanently mounted in my plane), I'm wondering: Might ADS-B ground stations be ignoring me with their traffic transmissions?
Last edited by CFIDave on Tue Nov 19, 2019 6:46 pm, edited 1 time in total.
Epic Aircraft E1000 GX
Former DA40XLS, DA42-VI, and DA62 owner
ATP, CFI, CFI-I, MEI
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Rich
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Joined: Mon Aug 30, 2010 12:40 pm
First Name: Rich
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Re: ADS-B effectiveness

Post by Rich »

CFIDave wrote: Tue Nov 19, 2019 6:18 pm Since my GTX335R is configured to broadcast that I don't have ADS-B IN installed (legally true, since there's nothing with ADS-B IN permanently mounted in my plane), I'm wondering: Might ADS-B ground stations be ignoring me with their traffic transmissions?
I think that's true. My KT74 was similarly programmed and I seemed to see the same thing. I changed the configuration to broadcast that I am "IN" equipped and ever since I get the TIS-R targets. My "IN" is also Stratus/FF. Don't ask - don't tell.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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