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ADS-B OUT in the US - now mandatory in transponder-mandatory airspace

Thx Jason.

Last Edited by Jujupilote at 13 Jan 20:14

alioth wrote:

Yes. The 30nm mode-C veil (or probably now renamed the ADS-B veil) requires it even if you’re in class G airspace and not within the lateral limits of class B above you. I think it’s also required if you’re flying underneath class C airspace now, but without diving into the FAR/AIM, I’m not 100% sure on that.

One can fly under the B or C airspace shelf as long as they are not within the 30 NM Mode C veil. For the B, there is little opportunity for this excepting a few B’s that exceed the mode C veil in size, examples are the LAX and SFO B areas.


…and the Mode C / ADS-B mandatory areas shown in the FAA graphic do not apply for any specific aircraft that has never had an engine driven electrical system, with the exception of over 10,000 ft, or within or above Class C or B airspace itself. In other words the Mode C veil does not apply, equally so for negative transponder etc. entry to Class D airspace within the Mode C veil.

It certainly seems that pilots are making use of ADS-IN (not mandated) but I wonder how long it’ll be before there’s any indication of FAA ATC utilizing the ADS-B OUT expenditure they mandated for the public, the supposed benefits of which were how FAA sold the program?

Last Edited by Silvaire at 13 Jan 20:33

If an aircraft is not equipped, it may make occasional use of the provision for obtaining ATC permission to fly into the rule airspace. This must be requested on the ground before flight and must be at least an hour in advance. I don’t think there will be many cases where a non equipped aircraft will be denied. Most of the US airspace below 10,000 MSL does not need ADS-B Out and in the Mountainous areas above 10,000 is permitted within 2500 AGL. So for most C172 and Piper Cherokee variants, they won’t be very affected if they remain clear of the B and C areas. Aircraft without an electrical power system are permitted to operate under the B.

This chart was from an FAA presentation on ADS-B Out and shows where one does not need ADS-B Out. Any point not covered in yellow or red is not required to equip unless for flight below 10,000 MSL and most of the yellow areas have shelves below which flight is permitted without needing ADS-B Out. So many pilots I know are unwilling to fly into a towered airport, much less a Class C or B airport and will never perceive a need to equip, Most of the US is ADS-B Out need not apply airspace below 10,000 MSL.


NCYankee wrote:

Aircraft without an electrical power system are permitted to operate under the B.

Or anywhere else outside of Class B or C airspace, not above Class C or over 10,000 ft, as I described, including all Veil areas without prior (or any) permission. The requirement is the lack of an engine driven electrical system, which includes aircraft with battery-only powered electrical systems that power the radio required for Class D entry.

Last Edited by Silvaire at 13 Jan 20:50

there is another way that makes adsb out exception easier to use called ADAPT

you have to go to scroll to blue block that says ADS-B equip push it then scroll down the list and you will see a topic that says ADS-B Equip in that list look for ADAPT push it, then you will see a prompt push it

also see a you tube video how to see ADAPT follow steps 1 to 4

KHQZ, United States

Ibra wrote:

our stuff is exempt but may have to remain OCAS

Do you have a reference to an EU regulation that allows such a requirement? (It’s not that I doubt you, but I want to read up on it myself.)

ESKC (Uppsala/Sundbro), Sweden

I’ve not heard of any EU move to mandate ADS-B OUT below 5700kg etc, in any airspace.

Shoreham EGKA, United Kingdom
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