Tailbeacon with obstruction

[Chrisgoesflying]

I already asked this question in another thread but kind of hijacked my own thread there and didn’t get a whole lot of answers, so here it goes again: I may have to fly into US ADS-B airspace more frequently from this fall. Obviously the cheapest and fastest solution is a tailbeacon (i don’t want the skybeacon as i just installed brand new led red and green wing tip lights). My Comanche has two tail lights. One is above the stabilator, the other one below the stabilator. I can’t install the beacon above the stabilator because it would interfere with the stabilator’s travel. so, can i install the tailbeacon below the stabilator or does the unit absolutely need an unobstructed view up for the gps to work?

 

[Kevin Holbrook]

Not an engineer or GPS expert, but I own a PA-24 and just looked at the stabilator area. The lower beacon will experience significant shading from the stabilator. There may be times when there are enough visible satellites to give a valid GPS signal, but I believe that you will not get reliable coverage. I have to think there will be significant amounts of time when there is no valid GPS position. And the system will notice that your ADS-B performance is not up to snuff.

 

[mondtster]

It would help if we knew what radios and transponder you currently have in order to make a recommendation for a path to compliance. But without knowing anything, I’d suggest the GDL82.

 

[MRC01]

IME, the TailBeacon GPS barely passes the FAA ADS-B performance test under ideal conditions. I had to install filters on the radios, modify the grounding at the tailplane, solder instead of crimp its power line, even replace the switches in my panel, just to get it to pass. After all this work it does pass, but only just. And this is installed at the top of the tail of my 172 without any obstructions. If there were any obstructions I can't see it passing.

 

[Chrisgoesflying]

It would help if we knew what radios and transponder you currently have in order to make a recommendation for a path to compliance. But without knowing anything, I’d suggest the GDL82.

1980s (and older) avionics so nothing that would get me close to compliance.

Transponder is a KT76A and radio is a SL40.

 

[mondtster]

1980s (and older) avionics so nothing that would get me close to compliance.

Transponder is a KT76A and radio is a SL40.

What is the latest information on Canadian ADSB compliance and do you intend to comply with their requirements at some point?

With what you’ve got for radios right now I can understand the desire for a simple add on means of compliance. You might be able to find a used GTX335 with built in GPS for cheap enough that it would be worth considering a transponder upgrade/replacement but a used GDL82 would probably offer the cheapest and most solid operation option for compliance.

Both the uAvionix beacon and the GDL82 are UAT compliance options, so another consideration is if you see yourself ever going where 1090 is required.

 

[Chrisgoesflying]

What is the latest information on Canadian ADSB compliance and do you intend to comply with their requirements at some point?

With what you’ve got for radios right now I can understand the desire for a simple add on means of compliance. You might be able to find a used GTX335 with built in GPS for cheap enough that it would be worth considering a transponder upgrade/replacement but a used GDL82 would probably offer the cheapest and most solid operation option for compliance.

Both the uAvionix beacon and the GDL82 are UAT compliance options, so another consideration is if you see yourself ever going where 1090 is required.

I am most likely moving to the US so Canadian compliance is not that important to me. The few times i will have to go to Canada, i’ll avoid ADS-B airspace. Plus, i think the earliest they’ll mandate ADS-B in airspace a GA pilot would typically fly in is 2028. They may change their mind 5 times by then.

 

[Racerx]

What is the latest information on Canadian ADSB compliance and do you intend to comply with their requirements at some point?

With what you’ve got for radios right now I can understand the desire for a simple add on means of compliance. You might be able to find a used GTX335 with built in GPS for cheap enough that it would be worth considering a transponder upgrade/replacement but a used GDL82 would probably offer the cheapest and most solid operation option for compliance.

Both the uAvionix beacon and the GDL82 are UAT compliance options, so another consideration is if you see yourself ever going where 1090 is required.

I believe NavCanada has softened on the diversity requirement and as long as you can pass a performance report in Canada you're good to go

 

[midlifeflyer]

Not an engineer or GPS expert, but I own a PA-24 and just looked at the stabilator area. The lower beacon will experience significant shading from the stabilator. There may be times when there are enough visible satellites to give a valid GPS signal, but I believe that you will not get reliable coverage. I have to think there will be significant amounts of time when there is no valid GPS position. And the system will notice that your ADS-B performance is not up to snuff.

Signal blockage is is pretty much the reason that the SkyBeacon (the one that replaces the strobes) cautions against installing in Comanches with tip tanks.

 

[Chrisgoesflying]

I think I found my solution. I'm looking to install a WAAS GPS soon anyways so when I do that, I'll get the Trig TT31, hook it up to the WAAS of the GPS and I should be ADS-B compliant. The Trig transponder is a direct slide in replacement for the KT76A.

 

[MRC01]

I am most likely moving to the US so Canadian compliance is not that important to me. The few times i will have to go to Canada, i’ll avoid ADS-B airspace. Plus, i think the earliest they’ll mandate ADS-B in airspace a GA pilot would typically fly in is 2028. They may change their mind 5 times by then.

Last I read, Canada ADS-B is satellite only, no ground stations, and required for GA only at 12,500' and higher.

 

[Chrisgoesflying]

Last I read, Canada ADS-B is satellite only, no ground stations, and required for GA only at 12,500' and higher.

That’s what they’re saying now. They’re planning to have something implemented for airspace around larger airports akin to the US at some point but nobody, including themselves know what exactly.

 

[Domenick]

My Warrior's tailBeacon has been flawless. I installed it, replacing the existing taillight, and ensured the ground connection jumping the rudder gap was good. Installed the app, adjusted the threshold once after the first flight based on the PAPR, and that's been it. Every few flights I request a PAPR. All good. But the unit is NOT shielded from the sky by the stabilator.