Transponder should be in ALT on ground

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Walboy

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It really depends on the airport, and your transponder. It used to be transponder off/stby upon landing. Many airports now request "on" for surface ops. It's on the ATIS quite often. We just keep ours in "AUTO"... :D
 
Always ON is the trend. I suspect the FAA is trying to condition people to leave them on for the benefit of controllers at airports capable of using the data.
 
And then in some places ATC will tell you off for having it ALT on ground.
Some airports explicitly request this in their remarks.
"ASDE-X SURVEILLANCE SYSTEM IN USE. OPERATE TRANSPONDERS WITH MODE C ON ALL TWYS AND RWYS."
 
Put it on stby,with proper code,switches to alt on takeoff.
 
I was told on my last BFR (last year) that the FAA has changed their tune. It is now discouraged to put the transponder into stby mode... just leave it ALT all the time. I believe I read somewhere that the GTX transponders actually transmit a GND code/altitude/airspeed while in GND mode.

I also flew with a DPE who was also on that same page. Confirmed that ALT is acceptable on the ground... which was a far cry from the instant failure years ago when I took my private checkride.
 
LDJones said:
Always ON is the trend. I suspect the FAA is trying to condition people to leave them on for the benefit of controllers at airports capable of using the data.
Click to expand...

It is. The FAA came out and started 'recommending' it about 4-5 years ago. The latest email is just s continuation of that push. I'm not sure why they don't just make it a requirement, but the wheels of govt are rather slow.
 
Mine's on ALT and it just stays there.

One less thing to worry about ...
 
Walboy said:
I asked the CFII who gave me my recent IPC whether or not my transponder should be set to ALT on the ground. He said "no" and wondered where I had heard that. The avionics shop who installed my GTN has the transponder programmed to switch from STBY to ALT when the groundspeed exceeds 30 kts and vice versa. Evidently avionics techs are under the same impression as the CFII.

According to this safety alert I received in an email today from the FAA, it says a transponder should ALWAYS be in the ALT position while moving on the ground at all airports.

The alert clearly says this applies to General Aviation (GA) aircraft. I just want to make sure that GA includes single engine piston aircraft in this situation. Do others interpret it that way?

http://www.faa.gov/other_visit/avia...afety/safo/all_safos/media/2015/SAFO15006.pdf
Click to expand...


" all operators and pilots..." Do you see any wiggle room there for specific types of operation?

Bob Gardner
 
Well, the linked document clearly says:

"This SAFO advises all operators and pilots of the need to ensure that transponders are in the altitude reporting mode whenever their aircraft is on an airport movement area at all airports." (bolded mine)

Nike had a slogan "Just Do It!" Some people on this forum see an FAA recommendation in a training document, AIM, or whatever, and seek to make a point that "It's not regulatory!" I've even seen it in a sig line! :rolleyes2:

Reminds me of a child shouting "You can't tell me what to do!"

I never was in the habit of activating my Mode C transponder until airborne, either manually or, more recently, automatically. Now that I know what the FAA wants, I'll change my habits to fall into line with their request.

Sometimes its just easier to go with the flow.
 
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Just a reminder... There are different kinds of transponder switches. Not all are alike. At least not mine.
 
ALT all the time.

My primary CFI told me the old way was STBY, then ALT when taking the rwy, and the new way was ALT all the time. And that was almost 10 years ago.
 
Speaking of this thread, is there a way to configure the Garmin 330 to stay in ""alt" mode? Mine is set to auto switch to "alt" at 30kts (I believe), but always resets back to "standby" on startup. I looked briefly at the installation manual, but I didn't see anything. It may also be an outdated manual, as my software version was updated a year or so ago.
 
First I've heard of this... I guess I can just leave it on ALT now.
 
ahkahn said:
I was told on my last BFR (last year) that the FAA has changed their tune. It is now discouraged to put the transponder into stby mode... just leave it ALT all the time. I believe I read somewhere that the GTX transponders actually transmit a GND code/altitude/airspeed while in GND mode.
Click to expand...
Wherever you read that was wrong. All of the Garmin transponders do ***NOT*** respond to interrogations when in GND mode. GND is the same as standby except that it will automatically switch to ALT when the transponder determines it's not on the ground anymore.
 
This is good news now I have a better excuse for when I leave it on alt the whole time.... High fives all around
 
Brad Z said:
Speaking of this thread, is there a way to configure the Garmin 330 to stay in ""alt" mode? Mine is set to auto switch to "alt" at 30kts (I believe), but always resets back to "standby" on startup. I looked briefly at the installation manual, but I didn't see anything. It may also be an outdated manual, as my software version was updated a year or so ago.
Click to expand...

I'm not sure that would be such a good idea for pilots who fly in the DCSFRA. You'd automatically be squawking an incorrect code as soon as you turned the avionics switch on,
 
flyingron said:
Wherever you read that was wrong. All of the Garmin transponders do ***NOT*** respond to interrogations when in GND mode. GND is the same as standby except that it will automatically switch to ALT when the transponder determines it's not on the ground anymore.
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330es manual,

Selects the standby mode. When in standby mode, the transponder does not reply to any interrogations. Pressing and holding the STBY key selects ground (GND) mode if Automated Airborne Determination is not otherwise selected from another source. When GND is annunciated, the transponder does not respond to ATCRBS interrogations but squitters and replies to discretely addressed Mode S interrogations.

Squitter outputs adsb position on ground in gnd mode
 
Going to standby was part of my after-landing procedure throughout my training and was exactly what I did on my checkride. This was all from late 2012-2014.

I think this discussion is the first I'm hearing of it not being the correct procedure.
 
cowman said:
Going to standby was part of my after-landing procedure throughout my training and was exactly what I did on my checkride. This was all from late 2012-2014.

I think this discussion is the first I'm hearing of it not being the correct procedure.
Click to expand...

Same.

There are a few times I've forgotten to switch from ALT to Standby after landing and nobody cared.

I guess I'll just leave it on ALT all the time now. I guess I'll have to look.. not sure if the 327 boots up in some default mode, or whatever you left it in when you powered down...
 
bobmrg said:
" all operators and pilots..." Do you see any wiggle room there for specific types of operation?

Bob Gardner
Click to expand...

I'm based at a towered airport that cannot see any transponder until the airplane is 500 ft in the air. Why? Because the airport doesn't have radar and gets the signal by microwave from the Class B 5 nm away. DIA can't see us until we're 500 AGL or so.

Fine, I'll put it on ALT as soon as I start the engine.
 
I think that SAFO is geared towards people that operate at airports that have ASDE-X and A-SMGCS. The whole point is so at a busy airport the ground controller can use the transponder signal to keep track of aircraft on the ground. At a small uncontrolled airport, the ATC isn't gonna do anything for you. The potential problem I could see is an aircraft equipped with TCAS on approach and landing could get a traffic/resolution advisory. Most TCAS disable audible warnings below a certain altitude on the radio altimeter. But getting a traffic call while breaking out of the clouds on an ILS into an uncontrolled field isn't something I want to get from a plane sitting holding short of the runway. My Opspecs say to turn it on while entering an active runway and off once clear of an active runway. That's what we do unless at a busy airport where it is told by us countless times to use it on the ground. Philadelphia Intl. and Louisville Intl. are prime examples. The airport remarks list this:"ASDE-X SURVEILLANCE SYSTEM IN USE. OPERATE TRANSPONDERS WITH MODE C ON ALL TWYS AND RWYS."
 
I have a 327 and it switches at 30 knots. Does anyone know if this setting can be changed to say 5 knots?
 
I have always left mine in ALT, and as Bob said wheres the wiggle room? The quoted and posted document from the FAA says to leave it in ALT mode. Why is there discussion about it?
 
jtheune said:
I have a 327 and it switches at 30 knots. Does anyone know if this setting can be changed to say 5 knots?
Click to expand...

From another forum*:

"The GTX 327 and 330 can be wired to automatically power on and resume last mode by wiring pin 1 to the avionics bus. Please see the installation manual wiring diagrams (last few pages in the pdfs) for the notes."

Rather than futz with that, I'm just changing my checklist.


*That similar thread here:http://ctflier.com/index.php?/topic/3302-faa-issues-alert-for-transponder-use/
 
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cowman said:
Going to standby was part of my after-landing procedure throughout my training and was exactly what I did on my checkride. This was all from late 2012-2014.

I think this discussion is the first I'm hearing of it not being the correct procedure.
Click to expand...

Flying Mag wrote about it in 2013:

http://www.flyingmag.com/technique/tip-week/use-correct-transponder-mode

The wording in the AIM regarding the use of transponders was modified last year. Regarding ground operations the AIM states: “Civil and military transponders should be turned to the “on” or normal altitude reporting position prior to moving on the airport surface to ensure the aircraft is visible to ATC surveillance systems.”
Click to expand...
 
tmyers said:
Why is there discussion about it?
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I think that the only reason that there is discussion is the way the FAA promulgated the change. It seems the word has been slowly trickling out over the last few years as evidenced by the number of CFIs and pilots who were completely unaware of the change.

The FAA needed to make a bolder announcement when introducing a change in practice that runs contrary to the way many pilots were initially trained. Think about all the guys that got their PPL 30-40 years ago and have barely cracked open the FAR/AIM since.
 
I would agree, but we all know the FAA is propelled by confusion, and If ever we meet remind me to discuss the call I got from the FAA this week.
 
Fearless Tower said:
The FAA needed to make a bolder announcement when introducing a change in practice that runs contrary to the way many pilots were initially trained. Think about all the guys that got their PPL 30-40 years ago and have barely cracked open the FAR/AIM since.
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But, the way I was trained back in 1974 is the correct way, no matter what the FAA says. :rolleyes:
 
tmyers said:
I would agree, but we all know the FAA is propelled by confusion, and If ever we meet remind me to discuss the call I got from the FAA this week.
Click to expand...

Oooooh, let's hear it.
 
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