ADS_B on all the time?

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PTAirco

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The general consensus around airport bums here was always: If you're not flying inside a Mode C veil area, you don't have to have it. Or if you have it, you're not obliged to turn it on. I hate to say it, but I was under that impression too. However FAR 91.225 states: (f) Except as prohibited in paragraph (i)(2) of this section, each person operating an aircraft equipped with ADS-B Out must operate this equipment in the transmit mode at all times unless - blablabla...

About the only exception would be special authorization or to fly somewhere to get it fixed.

So, it has to be on all the time. It does not say anything about the anonymous mode though - since it exists, I assume it's legal to fly outside the Mode C area while transmitting anonymously?

Discuss among yourselves.
 

TFF

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Anonymous is not anonymous to the FAA. It’s only anonymous to things like flight aware and plane to plane. It’s also only available on the lower altitude ADSB frequency types.
 

GeeZee

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Sorry TFF, but anonymous mode is anonymous to everyone including the FAA. You can stay anonymous as long as you aren’t “in the system” meaning if you file an IFR flight plan you have be identifiable. Just flying into a mode C veil doesn’t require that you change out of anonymous mode. I do it all the time.
 

GeeZee

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Interesting reading if you’re trying to combat insomnia ;)

And if you really really can’t sleep there’s always this.
paragraph 3.2.1.5.1.3.2 describes the method of deriving the “darn near” random ICAO code when anonymous mode is enabled. Note that this is generated at the source ( your ADSB Out box).
 
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TFF

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If you fly into a mode C veil, you are not squawking 1200; changing the squawk off of 1200 disables anonymous. If ATC directly pings your aircraft, it will show them. I know of accounts where the FAA were sending nasty grams to owners on airplanes on anonymous.
 

GeeZee

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“If you fly into a mode C veil, you are not squawking 1200”
Theres no requirement to talk to ATC or receive a discrete squawk code in a mode C veil. You do have to have a transponder and ADSB Out. Maybe you are thinking of class C airspace?
 

rv7charlie

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There certainly seems to be a poison pill in the ADSB rule, as written. With mode C, if the transponder fails, the plane is still legal to fly anywhere outside 'rule' airspace. On the other hand, once you equip with ADSB-out, it must be functional *everywhere, all the time*. FAA seems to have given us a couple of 'after the fact' exceptions (formation flight?), but my read is that if the plane has ever flown with ADSB, it cannot ever fly again without it being operational (barring special permission).
 

GeeZee

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I think that’s one of the biggies that got Martha Lunkin. She turned off her ADSB before flying under the bridge. She claimed it was some kind of electrical problem but the feeds weren’t buying it.
 

Kyle Boatright

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There certainly seems to be a poison pill in the ADSB rule, as written. With mode C, if the transponder fails, the plane is still legal to fly anywhere outside 'rule' airspace. On the other hand, once you equip with ADSB-out, it must be functional *everywhere, all the time*. FAA seems to have given us a couple of 'after the fact' exceptions (formation flight?), but my read is that if the plane has ever flown with ADSB, it cannot ever fly again without it being operational (barring special permission).
I *think* you can mark it "inop" or remove it entirely if it goes tango uniform. But if it is installed and functional, it MUST be on.
 
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