Interpreting the No-Electrical-System ADS-B Exclusion

wanttaja

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Ron Wanttaja
14CFR91.225 allows aircraft without electrical systems to operate in certain ADS-B rule airspace:

(e) The requirements of paragraph (b) [The basic requirement to include ADS-B Out] of this section do not apply to any aircraft that was not originally certificated with an electrical system, or that has not subsequently been certified with such a system installed, including balloons and gliders. These aircraft may conduct operations without ADS-B Out in the airspace specified in paragraphs (d)(2) and (d)(4) of this section. Operations authorized by this section must be conducted -

(1) Outside any Class B or Class C airspace area; and

(2) Below the altitude of the ceiling of a Class B or Class C airspace area designated for an airport, or 10,000 feet MSL, whichever is lower.


However, I'm having trouble parsing provision (2) above. (1) Says the aircraft must stay outside Class B or C airspace areas, but (2) seems to imply that aircraft without electrical systems CAN operate below the ceiling of Class B or C airspace areas ("operations...must be conducted...").

Section (d)(3) of the requirement is related, it says that ADS-B Out must be installed if the aircraft is to operate "Above the ceiling and within the lateral boundaries of a Class B or Class C airspace area designated for an airport upward to 10,000 feet MSL..."

To me, it'd be logical if the FAA doesn't want the non-electrical aircraft to operate between the top of Class B/C and Class E, but the wording of (2) above seems the opposite (since it says operations of the no-electrical-system-aircraft MUST be conducted below the altitude of the ceiling...).

Can anyone point to a clear explanation of the right interpretation? The same provision is in the transponder requirement (14CFR91.215), so it must have come up before.

adsb2.jpg
Ron Wanttaja
 
I imagine it like this:
I agree that's probably what they mean, but their wording is off. I would have worded it:

Operations authorized by this section must be conducted -
(1) [Unchanged] Outside any Class B or Class C airspace area; and

(2) Outside the area above the ceiling of a Class B or Class C airspace area designated for an airport, or 10,000 feet MSL, whichever is lower.


Ron Wanttaja
 
I think it just means you can go within the 30 mile veil where someone without ADS-B who has an electrical system can not.
 
Can’t go in, can’t go over,
As long as "In" refers to the Class B/C airspace *itself* (not the Veil), I agree that's what they intended. It's just not what they said....

I updated the FAA's diagram:
adsb2.jpg
Ron Wanttaja
 
I would also add a section of the B shelf that is outside the 30 NM mode C veil as under a B shelf is also a "no ADS-B Out required" area, with or without electrical power.
 
I think that Ron's got the right of it. If you haven't an electrical system you can go under the shelf, but not over and not in. I think not being able to go over isn't likely to be that big a deal, since most of those things don't normally go that high. Honestly, the rules haven't changed at all. They were always allowed under the self, at least as far as I know.

I think the biggest change is you used to be able to fly over without Mode C. Can't do that anymore.
 
I think it just means you can go within the 30 mile veil where someone without ADS-B who has an electrical system can not.
That's it. It removes the prohibition against flying in the veil outside of Class B and C airspace for aircraft without a certified electrical system. Nothing more complicated than that.
 
(2) seems to imply that aircraft without electrical systems CAN operate below the ceiling of Class B or C airspace areas ("operations...must be conducted...").
well, aircraft with electrical systems can do that so long as they are outside the 30 NM veil. The rule says aircraft without certified electrical system can do that within the veil. That's all.

the wording is unfortunate.
 
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Bunch of my buddies own a Luscombe over at the Class C. They have a battery on board for the transponder to get in and out of Class C, but currently cannot turn it off due to the ADSB restriction after exiting and before re-entering. Article and image linked below ...

https://www.aopa.org/news-and-media/all-news/2019/december/20/asking-for-ads-b
1220_Jim_Ivey_Luscombe8A.jpg
 
Bunch of my buddies own a Luscombe over at the Class C. They have a battery on board for the transponder to get in and out of Class C, but currently cannot turn it off due to the ADSB restriction after exiting and before re-entering. Article and image linked below ...

https://www.aopa.org/news-and-media/all-news/2019/december/20/asking-for-ads-b
1220_Jim_Ivey_Luscombe8A.jpg
It will be interesting to see how the FAA responds to the exemption request. Pilots with aircraft like this who are based inside a B or C are definitely in the "between the cracks" department.

Hope they had some great advice on drafting an "equivalent level of safety" SOP.
 
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The petition acknowledges that installing a wind-driven generator could power the transponder and ADS-B system, noting that it would not be an engine-driven system and that wind-driven systems are difficult to find today, likely would not generate enough power, and generally are unreliable.
Odd, there is/was an 8A with a wind alternator operating inside the DC SFRA...
 
Odd, there is/was an 8A with a wind alternator operating inside the DC SFRA...

A wind generator isn't the "engine driven electrical system", so it's exempt. Or are the SFRA rules different?
 
The point is that it was sufficiently powerful and reliable.
 
The point is that it was sufficiently powerful and reliable.

but we only know that in that particular case. Could be that it only provided enough additional power for 2 hours, or only in daytime operations if they are have lights also.

Brian
 
but we only know that in that particular case. Could be that it only provided enough additional power for 2 hours, or only in daytime operations if they are have lights also.
One of our Fly Baby guys installed a Gennipower wind generator. Good for ~4 amps at 70 MPH. Kind of marginal for a transponder, when you want to run a radio and charge the battery for starting.

http://www.bowersflybaby.com/tech/wind2.html

Ron Wanttaja
 
I think post #2 is correct.


The FAA is trying get every RC airplane above 0.55 pounds in weight to carry the equivalent of ADS-B. Why can't a hang glider or J-3 carry one of those? 1/2 :)

Ron Wanttaja

People who fly RC planes have more money . :)
 
Someone may have posted this in another thread, but the FAA has discovered Google Earth. There are several KML files for download. They all disclaim that they shouldn't be used for navigation, but the overlays for ADS-B airspace are very good.

Open Google Earth, click File->Open, and load in this KML file. Might take a minute; it's huge. Once done, it appears in the left pane and you can select Class B and C airports in the USA. Nice.

Direct link for download: https://www.faa.gov/nextgen/equipadsb/research/airspace/media/2020ADS-BAirspaceMap.kmz
 
Someone may have posted this in another thread, but the FAA has discovered Google Earth. There are several KML files for download. They all disclaim that they shouldn't be used for navigation, but the overlays for ADS-B airspace are very good.

Open Google Earth, click File->Open, and load in this KML file. Might take a minute; it's huge. Once done, it appears in the left pane and you can select Class B and C airports in the USA. Nice.

Direct link for download: https://www.faa.gov/nextgen/equipadsb/research/airspace/media/2020ADS-BAirspaceMap.kmz
I didn't find it particularly helpful. Didn't give me any more information than a Sectional. Less actually. The first thing I did to check it out was look at an airport under a Class C shelf. The FAA Google map would lead one to believe the airport was in ADS-B airspace. The Sectional, which shows the Class C altitudes, shows it is not.

But perhaps I'm not using it correctly. Try my experiment in your area and see what you get.
 
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The FAA has a requirement that is totally based on a very high tech implementation.
The solution doesn't work with low or no tech aircraft.
The last time I flew into a class "D" airport with a buddy in his Aeronca Chief, the batteries in my handheld had died.
I called the tower on my phone to tell them where we were, and the young lady in the tower was pleasant, but totally freaked out because even though we were only 4 miles away they could not see us on radar. At certain airports I have a similar problem in the Cub. It's invisible to certain types of radar. Don't know why, I'm not a radar guy
So here is the issue in a nutshell. I have no electrical system, no radio, nothing.
Even if I do wander into a "no fly" zone will they even be able to see me? How are they going to know who it is, and how are they going to contact me to let me know I'm a bad boy?

IMHO, at some point the FAA is going to mandate electrical systems, and ground everything that doesn't comply.
 
The FAA is trying get every RC airplane above 0.55 pounds in weight to carry the equivalent of ADS-B. Why can't a hang glider or J-3 carry one of those? 1/2 :)

Ron Wanttaja

Ron, under the current rules, you can't add the required transponder to a model plane, the plane has to come from the manufacturer with the transponder already installed.

Pretty short sighted, but very bureaucratic.
 
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