ADSB preflight check

[donjohnston]

Just saw this on AvWeb.

https://www.avweb.com/aviation-news/ads-b-preflight-requirement-issued/

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.

There's a website which you can use to determine if there are outages along your route of flight which if you use it, that will qualify at sufficient due diligence. But with no login, I'm not sure how you're supposed to prove that you used it. (maybe a screen shot? )

https://sapt.faa.gov/outages.php?outageType=129001250&outageResolution=0.5

Looking at the map for today, it looks like the entire state of Florida (and AL, GA, SC & VA) would be a no-fly zone.




Excellent plan FAA!

 

[bnt83]

W.T.F.

 

[donjohnston]

It really does confirm...

The FAA; We're not happy until you're not happy.

 

[woodchucker]

Those orange bubbles are apparently GPS interference testing. Uncheck the box below to see them go away. It appears red indicates outages, but I don’t see a legend showing that. Here is an example I found by playing with the time slider.

 

[Challenged]

"ADS-B operators having aircraft equipped with TSO–C129 (SA-On) approved GPS receivers that do not meet the performance requirements of TSO–196 or TSO–C145/146, the operator must run a preflight prediction."

TSO-C129 and TSO-C196 refer to non-WAAS GPS systems.
TSO-C146 refers to WAAS-enabled GPS systems.

Is this similar to using a non-WAAS GPS and monitoring for RAIM failures?

 

[Let'sgoflying!]

If atc is happy, I'm happy.

 

[kyleb]

So, WTF do you do if the equipment isn't likely to work? I can't see Delta or American cancelling flights, and it makes little difference to me if it works or not.

This seems like a huge waste of my frickin' time.

 

[deyoung]

So, are you just required to check and be aware where outages are, or are you not allowed to fly through any outage? That seems both vague and ridiculous....

 

[dans2992]

Can you use a non-WAAS GPS for ADS-B?

 

[Challenged]

I found some random post on the Internet says: "It is permissable (sic) to use a non WAAS GPS source with your transponder if you wish to voluntarily transmit ADS-B in airspace where the mandate does not apply."

 

[deyoung]

So, no, except in airspace where you wouldn't care anyway. Right?

 

[Sundancer]

I'm a statistical anamoly, having never found an avionics failure on preflight - all the ones I've experienced have occured enroute.

 

[RingLaserGyroSandwich]

I think the clarification in this article resolves the issue: https://www.avweb.com/aviation-news/faa-clarifies-ads-b-preflights-ga-is-exempt/

The FAA will issue a Notam on Thursday that will essentially exempt general aviation aircraft operators from an ADS-B preflight requirement when the ADS-B mandate kicks in next January.

Of note, "the preflight requirement was always intended for airliners" and "he suspects the WAAS exemption got lost in the extensive vetting process that policy statements like the preflight requirements included in the recent Federal Register Notice go through."

 

[cowman]

I think the clarification in this article resolves the issue: https://www.avweb.com/aviation-news/faa-clarifies-ads-b-preflights-ga-is-exempt/



Of note, "the preflight requirement was always intended for airliners" and "he suspects the WAAS exemption got lost in the extensive vetting process that policy statements like the preflight requirements included in the recent Federal Register Notice go through."

Sounds right, as obnoxious as the FAA can be they usually don't issue edicts that make a large percentage of flights impossible.

 

[John Collins]

Can you use a non-WAAS GPS for ADS-B?

Yes, but there are no non-WAAS position sources on the market for GA. In the case of Airliners, they use non WAAS GPS position sources and have. These are the ones that need to check for RAIM availability. The airlines also use position sources that provide all the data necessary to be used with an ADS-B Out transponder. The non WAAS GPS systems used by GA do not support the data elements needed by ADS-B out and It was economically not feasible to upgrade them. Even if this was done, the non WAAS GPS would not satisfy the requirements to as high a percent as WAAS and RAIM would have to be checked before every flight. AC 20-165B describes the technical requirements for using a TSO C129, TSO C196 or TSO C145/146 position sources used with ADS-B Out. TSO C129 is for the original non WAAS GPS (Position Source or Navigator). It was superseded by TSO C196 for non WAAS GPS (position source only). TSO C145/146 are for WAAS (Position source/Navigator respectively).