ADS-B and the essential bus

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Rich
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Joined: Mon Aug 30, 2010 12:40 pm
First Name: Rich
Aircraft Type: DA40
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ADS-B and the essential bus

Post by Rich »

The skybeacon setup (powered by the nav light circuit) got me pondering about this, but I think some of the other ADS-B out approaches would have the same behavior:

I'll start by saying that, in my DA40, the essential bus and essential avionics bus came with no spare breakers/circuits. Included in the list of equipment on it is the transponder and Com1/Nav1, which is my 530W. This means that on the essential bus I would have mode C/S and 1090 ES, should I come be running on the EB. Since ADS-B in is provided by the battery-driven iPad/FF/Stratus, I would continue to have ADS-B out and in.

What is not on the essential bus is the nav light circuit, which means should an approach like the skybeacon be used, it would drop out when running on the essential bus. But the transponder would still be usable. It occurred to me that some of the other approaches that add another powered device to provide ADS-B out (and even in) may wind up with the same situation.

While loss of this capability when on EB may not be critical, it'd be worth knowing ahead of time what the effect of being on EB would be in the plane you fly to avoid mental distraction when you may already be in a semi-emergency situation.
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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