Transponder/Airspace Question

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kyleb

Final Approach
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Drake the Outlaw
Remind me. Since I don't have ADS-B out installed, is there any reason *not* to just yank out the transponder? I can't think of what airspace benefits i get by only having the Txp.
 
kyleb said:
Remind me. Since I don't have ADS-B out installed, is there any reason *not* to just yank out the transponder? I can't think of what airspace benefits i get by only having the Txp.
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While a transponder is not required for flight following it sure makes getting flight following a lot easier ...
 
Daleandee said:
While a transponder is not required for flight following it sure makes getting flight following a lot easier ...
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Honestly, that was one of two things I could think of. The other is/was having the TXP could help in the case that I went missing enroute.
 
kyleb said:
Remind me. Since I don't have ADS-B out installed, is there any reason *not* to just yank out the transponder? I can't think of what airspace benefits i get by only having the Txp.
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91.215 ATC transponder and altitude reporting equipment and use.
 
Clip4 said:
91.215 ATC transponder and altitude reporting equipment and use.
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Is there something in that mess I'm not thinking of? I can't think of a thing I would lose from an airspace perspective (which was the original question), and without reading through that document and 10 others it lists for reference...
 
luvflyin said:
It helps in you being called as traffic to other planes
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It also allows other aircraft with ADS-B to be directly aware of your position as well, depending on your proximity to an appropriate ground station.
 
In my opinion a transponder with mode C makes the job of air traffic control easier and helps to make the airspace work more efficiently.

Without a mode C transponder operating; to air traffic control I am a radar target with no altitude information.


As ADSB becomes more popular the transponder being used makes you more visible to other aircraft who have ADSB in.
 
Even without ADS-B on board, in certain areas to include the East Texas boon docks where I fly most, I can see I identified aircraft on my fish finder. If you are seen squawking VFR by radar, it is indicated on my fish finder as an unidentified aircraft. If you are on flight following, you will be identified by tail number also.

Although it is only a microscopic amount of safety level involved, IMHO removing an operational transponder is making you less electronically visible.

If the Xponder is operational, even if not tested, I am struggling to figure out what advantage there would be in removing it

When flying around directly above our little airport for several hours a few years ago owing engine break in, I spent lots of time just observing aircraft both with the naked eye and on the fish finder. I was surprised then when I learned that aircraft without ADS-B installed were showing up on the fish finder. I know many people at our airport and knew who did and did not have it. I even confirmed a few of them by asking them.

The effectiveness of ADS-B is debated constantly. I suppose that a similar debate could be had regarding Xponders, but why remove a working transponder?
 
The original question has been answered (I think). There are no airspace advantages to keeping the transponder.

I have the ADSB unit in a box in the basement, so the next step is to remove the Txp to investigate how easy I made it to remove the Txp tray when I installed it 20 years ago. After that, well, we'll see... Is the tray a weekend laparoscopic replacement through (and from under) the panel, or will I need deeper surgery (panel removal) to get the old tray out and the new one in?
 
I have not read the regs in a while.
I thought there was some edge cases where transponder is required and ADS-B is not. That is what I would check for.

Tim

Sent from my HD1907 using Tapatalk
 
kyleb said:
is there any reason *not* to just yank out the transponder?
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kyleb said:
so the next step is to remove the Txp to investigate how easy I made it to remove the Txp tray
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FWIW: If pulling the xspndr may consider leaving the harness installed and intact for future use or aircraft sale. On several aircraft that didn't need need an active xspndr we'd remove the radio/antenna/encoder, install rack cover plate, disconnect the pwr/grd, and stow the harness. If you need that panel space for something else disconnect the rack plag/back plate and remove rack. For example, had one aircraft where xspndr was swapped for a marine radio 4 months out the year and left both harnesses in aircraft.
 
I created another thread on here regarding regarding repairing my transponder even though I don’t have ADSB. I’m glad I did it. I show up as a TIS-B target quite often to other aircraft, and the job of ATC is much easier. I didn’t like being a nuisance primary target for ATC. At least they’ll have an unverified altitude to pass along even when I’m not on frequency.
 
So, the consensus has gone from "ADSB Sucks and only weenies need to look at a screen to see other traffic" to:

"Oh, Dear God, if you don't show up on a screen somewhere, you're endangering everyone!"?

None of which really has to do with the airspace issues I was trying to verify/validate.
 
kyleb said:
So, the consensus has gone from "ADSB Sucks and only weenies need to look at a screen to see other traffic" to:

"Oh, Dear God, if you don't show up on a screen somewhere, you're endangering everyone!"?

None of which really has to do with the airspace issues I was trying to verify/validate.
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There’s no airspace benefit to the transponder in the U.S. Flying into Canada on the other hand, the transponder provides some benefits for now.
 
kyleb said:
So, the consensus has gone from "ADSB Sucks and only weenies need to look at a screen to see other traffic" to:

"Oh, Dear God, if you don't show up on a screen somewhere, you're endangering everyone!"?

None of which really has to do with the airspace issues I was trying to verify/validate.
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Lol. I didn't get the feeling that anyone was pushing it that extreme. Just pointing out that it does make you more visible, electronically speaking, to others. But yeah, I get your POAian take on it.:biggrin:
 
So you only want to operate out of D, E, and G airports that reside outside of all Mode C Veils, and you never want to fly over 10,000 MSL?
 
write-stuff said:
You won't be able to easily get flight following in Class E airspace without a transponder.
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I think he means the original question. Just wanted to know what pieces of sky he could or couldn't fly in. All the flight following stuff came later.
 
What ADSB do you have in a box? The tail beacon does NOT connect to the transponder if that is what you have.. they work to together to keep your presence known to one and all.There is no advantage to eliminating the TXP. Having a TXP and ADSB provides the ability to use all available airspace hassle free. However I managed to reposition a 172 with out ADSB from California to Texas trouble free. Just took a bit of extra flight planning.
 
BoButt said:
The tail beacon does NOT connect to the transponder if that is what you have
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It is connected through the power lines and reads the "noise" on the power lines to determine your squawk code and mode C altitude.

https://uavionix.com/products/tailbeacon/
"uAvionix’s patented power transcoder technology seamlessly communicates with your existing legacy transponder over your aircraft’s electrical system."
 
BoButt said:
What ADSB do you have in a box? The tail beacon does NOT connect to the transponder if that is what you have.. they work to together to keep your presence known to one and all.There is no advantage to eliminating the TXP. Having a TXP and ADSB provides the ability to use all available airspace hassle free. However I managed to reposition a 172 with out ADSB from California to Texas trouble free. Just took a bit of extra flight planning.
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I don't have a tail beacon. Installed is a 20 year old King transponder. It will have to come out to install the new Appareo Stratus ESG that is in the basement. My fundamental question was what airspace rights will I give up if I uninstall the current TXP. The answer is none, far as I can tell.

Uninstalling the current TXP eliminates the need for the biannual TXP check which is due either in May or June this year (need to check the logs). And it allows me to do a rolling tear-out of the old tray, encoder, wiring etc. Hopefully, I won't have to pull the entire panel to remove the King tray and install the Appareo tray. What I didn't want to get into was a situation where if it takes a month to get through the transformation, I'd suffer unacceptable airspace losses. That doesn't appear to be the case. Instead, I'll be able to fly anywhere I can fly today (which is already somewhat limited), but can make incremental process towards the ADSB upgrade.
 
Capt. Geoffrey Thorpe said:
It is connected through the power lines and reads the "noise" on the power lines to determine your squawk code and mode C altitude.

https://uavionix.com/products/tailbeacon/
"uAvionix’s patented power transcoder technology seamlessly communicates with your existing legacy transponder over your aircraft’s electrical system."
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And even if the power connections on the transponder are well filtered, I imagine that the power wires would act as an adequate antenna for the tailBeacon to receive the radiated transponder signal.

With the integrated WAAS GPS in the tailBeacon, does it even need the Mode C altitude from the transponder?
 
Palmpilot said:
With the integrated WAAS GPS in the tailBeacon, does it even need the Mode C altitude from the transponder?
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As I understand it the two altitudes have to agree (or be made agreeable) so the ADSB unit needs to know what the transponder is reporting. I also understand that pressure altitude is more precise than GPS altitude.

I asked a similar question when I was going to install a package deal that included a used Garmin 327 and GDL 82 unit. The package didn't include an altitude encoder. I emailed the seller and was told that an encoder was not required. I later learned that was incorrect.

I ended up with a Garmin 320A with encoder and the uAvionix echoUAT + skyFYX-EXT GPS unit that supplies "in" and "out" and does not require a physical connection to the transponder/encoder.
 
Capt. Geoffrey Thorpe said:
Regulations require the mode C.
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Does ADS-B report both the mode C and the WAAS altitudes?

The reason I'm wondering is that the Montezuma Castle folks have been using some kind of ADS-B receiver to hassle pilots who were overflying their non-restricted airspace, and there's a question in my mind about how far off their altitude readouts may be if they don't have a means to correct the mode C readouts for the current altimeter setting.
 
I do not have an alternator or generator. Only hand held com with outside antenna. Happy as a calm at high tide.
WILL
 
Next chapter of the story:

I spent about 20 minutes this evening with an Allen wrench and a couple of screwdrivers. I pulled the TXP and the adjacent (recessed) Garmin 695, with the intent of "just taking a look" at how I'd installed things 20 years ago. The reconnaissance turned into action, and I removed all the screws attaching the TXP tray to the avionics rails. That could have been trouble, but wasn't. Much easier than I expected. Tomorrow, I'll go back to the airport at lunch with the right tools (primarily a screwdriver with a long reach) to pull the 3 screws which attach the harness and the connector to the TXP tray. I *think* the TXP tray will come out pretty easily after those 3 screws. Oh yeah, I need to disconnect the antenna too...

This looks like it'll be easier than I thought it might be.
 
kyleb said:
So, the consensus has gone from "ADSB Sucks and only weenies need to look at a screen to see other traffic" to:

"Oh, Dear God, if you don't show up on a screen somewhere, you're endangering everyone!"?

None of which really has to do with the airspace issues I was trying to verify/validate.
Click to expand...

You need to think of the children!!!
 
TXP removal - Chapter 3.

Spent about 20 minutes in awful contortions under the panel cutting zip ties and unhooking the TXP antenna cable. Removed the final 3 connectors holding the strain relief to the tray and the harness to the tray. The time under the panel suuuckkkked. Getting under there was bad enough when I was 35. At 56, it isn't any fun at all. Tonight, I need to extract the Appareo from the basement and see what will be required to install it where the King tray was. I'm sure the front rail attachment structure will work. I hope I can make the rear hard point(s) work without making significant sub-panel changes.

Figure that out, do the wiring from the Encoder to the TXP/ADSB device here at the house, and maybe I get to install the thing in a few days.
 
TXP removal - Chapter 4. Removed the encoder and all associated wiring tonight. 1.5 hours of laying on my back under the panel. I brought more padding tonight, but it still sucked. I mistakenly clipped 3 wires I didn't intend to clip, so re-terminating 2 of them and splicing the other is the first order of business tomorrow morning. Yuck.

On the good side, I did confirm that the mount tray for my old ACK encoder works on the updated ACK encoder too. Yay. At least I won't have to install a new mount under there.

And reached out to Stratus today asking for a little help with wiring diagrams. Their install manual points you to the encoder supplier's info and the encoder supplier's manual points you right back to whoever provided your ADSB unit. A veritable circular firing squad, but no bullets in the respective guns. They responded to my email, but again pointed to ACK for the info. I replied that since the ACK units are by far the most common encoders, why not have someone spend 30 minutes and type up a how-to to connect that specific encoder to make things easier for their customers. Seems like it would be a marketing advantage for both ACK and Stratus to have a set of step by step instructions...
 
Reasons for keeping your transponder.

1) Although you don't get traffic advisories, other aircraft, either ADS-B Out/In equipped, TAS or TCAS equipped will see you as traffic.
2) If you have an occasional need to fly into ADS-B required airspace, to obtain permission, ATC will require you to have a transponder.
 
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