ADS-B question


Well-Known Member
It seems like getting ADSB was a big deal for everyone to get compliant by Jan 2020 and ever since I havent heard anything. Is it just built into the flight planning software or do you have to go run a check somewhere else? Has anyone ever gotten a check that didn't pass?


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Been wondering the same thing and haven't been given a good answer. Our flight planning software does a RAIM and ADS-B check when we release the flight. We were initially directed to check the ADS-B prediction tool from the FAA if we get a failure. Haven't had much guidance as far as what to do with that info. I've routinely seen short term outages ~15 mins over major airports (ORD/IAD/NYC) and have never seen a "ADS-B ground stop" soooooooo IDK.


Well-Known Member
Depends on the hardware installed on the aircraft, if the aircraft is equipped with a TSO C145/146 compliant ADS-B receiver you should generally be fine. Other older models of ADS-B hardware such as those that are TSO-C129 compliant, you can run into temporary ADS-B coverage/performance issues in certain areas that will require a reroute or a delay until sufficient coverage is available.
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Delta Echo

Well-Known Member
Airline fleets only have to have an ADS-B out link to show flight specific information to others. They do not have to ADS-B in that accepts inbound form other flights.


Well-Known Member
Our aircraft are equipped with SBAS so availability prediction is built-in. The FAA will issue a NOTAM if SBAS in affected in some way, so our primary preflight availability check is accomplished by checking them (unlike RAIM). Secondary checks can be accomplished manually via our flight planning software or


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It depends on the types of position source you have in the GPS, and if you have Exemption 12555.

If you are SA-Aware equipped (newer GPS systems) and have Exemption 12555 - you have until 2025 to become SBAS equipped. NO preflight actions are required unless ADS-B is inop, when in that case call the command center for clearance to operate, like in the case of a no-transponder (both are inop aircraft).

If you are SA-On equipped, or SA-Aware without 12555 you are required to perform a preflight validation of the GPS coverage, and in all the flight planning system cases, there is a capability (if your carrier contracted it) to have the preflight validation ran in the flight planning system behind the scenes. If ADS-B is inop, call the command center for clearance to operate, like in the case of a no-transponder (both are inop) aircraft.

If you are SBAS equipped you're at the end state and you're done.

I was on the Equip2020 Taskforce coordinating the aviation response to the mandate from 2015-Dec 2019, so unfortunately I know way too much about it. The ADS-B MMEL Policy letter is being amended to reflect the relief the regulation provides and is in internal FAA coordination before it goes up for public comment, I wrote that too.