ADS-B Preflight Requirement Issued (Clarified)


Some pilots and operators will have another series of preflight checks to conduct when the ADS-B mandate kicks in on Jan. 1. The FAA says in a new policy statement it will be up to pilots and operators to make sure the gear will actually work along their predicted flight path. As part of the flight planning process, operators will be required to exercise “due diligence” in the form of a “preflight availability prediction” to make sure that an adequate GPS signal is available for the ADS-B Out to function properly for the full flight.

In most cases, the due diligence requirement will be satisfied by checking the FAA ADS-B Service Availability Prediction Tool (SAPT) for the intended route. Doing so creates a record in the SAPT system that the preflight work has been done. The check is targeted mainly at those equipped with non-WAAS GPS receivers because they’re more vulnerable to service disruptions that make ADS-B less reliable. The FAA also notes that if the GPS status changes while the flight is in the air or the SAPT itself is unavailable, pilots will not be sanctioned for noncompliance with the ADS-B requirements. Likewise, if weather or other circumstances require deviations into areas where GPS is unreliable, pilots will get a pass. When planned or known GPS disruptions occur, the FAA will issue a Notam.

An earlier story, based on the FAA Policy Statement, mischaracterized the scope of the preflight requirement and the FAA is supplying further guidance on its applicability.

Russ Niles
Russ Niles is Editor-in-Chief of AVweb. He has been a pilot for 30 years and joined AVweb 22 years ago. He and his wife Marni live in southern British Columbia where they also operate a small winery.

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  1. “When planned or known GPS disruptions occur, the FAA will issue a NOTAM.”

    So, here we go. Enormous, at-random virtual TFRs because the FAA’s vaunted “surveillance” system is unreliable.

    “I told you so” is SO unsatisfying.

    • This is “not my job” as a pilot.
      ADS-B out is for the benefit of ATC, not as part of my job as a pilot to arrive at Point B.

  2. Yep, a bunch of overpriced overcomplicated crap that barely works and they are perhaps kind enough to waive sanctions as long as we all jump through sufficient hoops.
    Sounds like the FAA and the third class medical.
    What a mess that all was, and this will be. Time to get some reasonable management at the FAA. I should have applied.

  3. So, even though on 1/1/2020 ADS-B is only required where Mode C is currently required, one can not make a flight to anywhere unless ADS-B is operational for the entire flight??? SNAFU

  4. And on a related note, I see Europe’s Galileo GPS system has been down since Friday:

    “Engineers worked around the clock over the weekend but there is no update yet on when the service will resume.
    The problem means all receivers, such as the latest smartphone models, will not be picking up any useable timing or positional information.”

  5. So, beginning January 1, the FAA will expect me and all other pilots of ADS-B-equipped aircraft to check my route for GPS integrity. The ironic thing is that predicted outages are almost always “GPS Interference Testing” — a deliberate government interruption of the very service that the FAA will demand I verify!

    AOPA is the only organization I know of that is fighting indiscriminate, perpetual “GPS Interference Testing”. Almost nobody else cares — not even the pilots in Congress!

    • Highly annoying for sure, but we tend to forget all us civilian users are piggybacking on a military system. In a real war with another technologically advanced country we don’t want our own military blindsided by loss of capability they didn’t scope out in advance.

      Now, you certainly could debate the wisdom of creating this sort of conflict in the first place, but that’s another subject.

      • It’s not an accident that the military commander in chief is a civilian. So the military spent our tax money on it, but that does not make it their property. It belongs to the USA and it’s people.

  6. So…we spent thousands of dollars on our King Air to have not one but two ADS-B transmitters installed, and when there’s an outage the enforcement letter comes to me? We did our part to comply with the upcoming regulations – it seems like if the system is unreliable, that should be on whoever maintains it. But at least they’ll issue NOTAMS! Just for fun, I counted the number of (mostly unintelligible) GPS NOTAMS for my 300nm flight tomorrow – 91 of them. I foresee the FAA ending up in court real soon after the first violations are issued.

    • One NOTAM per 3.3 nm of flight. Sounds like you could spend as much time reading the advisories, as you would spend flying the route.

      What’s wrong with this picture?

  7. It’s always the pilot’s fault.
    We go out for some pattern work, or a short hop for a $100 hamburger and we have to “do” this ADSB check first — on a website that has no guidance or steps to follow — or way to see that the system “has” a record that we checking the ADSB system!
    Typical bureaucratic mumbo jumbo.
    They didn’t let us know about this ADSB “make work” scheme years ago … otherwise more pilot’s would have given up on installing the expensive ADSB equipment.
    What’s next, making pilot’s check that radar is working in their area prior to any flight where they might use radar?

  8. After they “FAA” can’t come to a common sense idea on how to handle RC models “they call drones” they flip out and come up with a rule that is bound to put that entire industry out of business. Now they’ve come up with this wet dream of stuff rolling down hill and right into our laps so they’re blame free and we’re stuck with needing the proof we went over and above to comply for a system that should never need this type of compliance in the first place. Who the H@ll is allowing this type of run away mentality over there? Sounds very much like retired incompetent military mentality going unchecked and unchallenged. Like someone here already said, this is heading to court the first time they try to enforce it……I hope!

  9. “The check is targeted mainly at those equipped with non-WAAS GPS receivers because they’re more vulnerable to service disruptions that make ADS-B less reliable.”
    Show me an approved ADS-B out transmitter that doesn’t have either a built in WAAS receiver or has a WAAS position data in stream and I’ll show one that doesn’t comply with the TSO!

    Why do you think we’re having so much trouble with the old ELTs re-radiating Comm transmissions that blow away the WAAS signal? See the final check out in the Garmin install manual for the freqs that are troublesome.