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G3X 9.12/9.22 verbose traffic alerts

F

FitzRX7

Well Known Member
I'm just getting around to flying on 9.22 (*edit, 9.14, because fat EIS) and I have now 2 or 3 times on short final had a very lengthy audio alert for traffic clearing the runway. I'm not a big fan of this, as it has the potential to distract or block an important radio call. Previous versions just said "traffic, traffic" which was bad enough and I don't think inhibiting below a certain AGL altitude is in the cards like in certified TCAS systems.

Curious if anyone else has had this issue?

Also wondering if we could have a way to disable the "Improved traffic audio alerts" but keep the basic "traffic, traffic"?

Thanks!

Fitz
 
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You're not alone! I've submitted this to Garmin as a feature request, and their response was, that's a surprise, people wanted it.

I expressed an opinion like yours. I may have traffic callouts turned off completely in my system, don't remember, but better that than distracting chatter.

In the NASA ASRS reports database, I have over the years found four cases in which the Honeywell RAAS (runway awareness and advisory system, a system which generates voice callouts about every detail of progress taxiing) interfered with ATC communications, and I told Garmin (G3Xpert) about that.

When I worked at Boeing, studying runway incursions, I got a RAAS demo flight and came to the conclusion that it was, "Gee, what feature can we sell and hope that somebody will buy it." I knew some of the RAAS development team from when they were upstairs from me when I worked at Honeywell on FOQA systems. Their cynical joke was that management told them to add features to the enhanced ground prox system or it will be "our ***." (obvious pun)

I also wrote the first draft of expanding the Boeing "quiet, dark cockpit" philosophy to voice callouts, when they were appropriate and for what situations, and when not.

So you're right, too many voice callouts can be deleterious.
 
I'm brand new to the G3X system and the agree that traffic alerts on short final for airplanes on the ground are unwanted and potentially dangerous.

I believe it was the a plane at the hold short line that set mine off.
 
Thanks for the replies y'all.

Yeah I had to set Traffic Alerts to disable for now unfortunately. Maybe we'll get it as an option soon!
 
I see this in my G3X system as well. I would guess most new transponders (I know Garmin does) set themselves to standby below a set speed, which should reduce this problem. People who don't have transponders which are automatic, need to remember to switch their transponder modes before takeoff and after landing.

I don't know how the bolt on ADSB tail / wingtip beacons work with the transponder. They have become popular do to the low cost of retrofit, but do they stop transmitting on the ground?
 
Ezburton said:
I see this in my G3X system as well. I would guess most new transponders (I know Garmin does) set themselves to standby below a set speed, which should reduce this problem. People who don't have transponders which are automatic, need to remember to switch their transponder modes before takeoff and after landing.

I don't know how the bolt on ADSB tail / wingtip beacons work with the transponder. They have become popular do to the low cost of retrofit, but do they stop transmitting on the ground?
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Not sure, but do not believe this is the case. In my garmin and grt systems, the go into “grd” mode while on the ground. That is NOT the same as standby. The transponder is still replying to atc interrogations, but the adsb messages in that reply say ground. I think These type of messages are going to be retransmitted by the tis-b system, but not sure. As to the less sophisticated systems i am pretty sure just about every pilot turns the transponder to alt at startup or after a short warm up period. Never seen guidance to the contrary and assumed atc wanted it this way.
 
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lr172 said:
Not sure, but do not believe this is the case. In my garmin and grt systems, the go into “grd” mode while on the ground. That is NOT the same as standby. The transponder is still replying to atc interrogations, but the adsb messages in that reply say ground. I think These type of messages are going to be retransmitted by the tis-b system, but not sure. As to the less sophisticated systems i am pretty sure just about every pilot turns the transponder to alt at startup or after a short warm up period. Never seen guidance to the contrary and assumed atc wanted it this way.
Click to expand...

IIRC, ground mode on ADS-B is driven by an external switch, such as a squat switch. Pretty sure that our plain vanilla ADS-B units don't have that.
 
Ed_Wischmeyer said:
IIRC, ground mode on ADS-B is driven by an external switch, such as a squat switch. Pretty sure that our plain vanilla ADS-B units don't have that.
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Not correct, these systems use a variety of inputs for air/ground determination.
 
lr172 said:
As to the less sophisticated systems i am pretty sure just about every pilot turns the transponder to alt at startup or after a short warm up period. Never seen guidance to the contrary and assumed atc wanted it this way.
Click to expand...

Here's a 2013 aricle describing when the AIM guidance was changed to using ALT on the ground as well as in the air.

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

Also, IIRC, the advent of ADSB has changed the OSH NOTAM to transponders on for the arrival.
 
mburch said:
Not correct, these systems use a variety of inputs for air/ground determination.
Click to expand...

I'm trying to find detailed information on ADS-B to fill in my knowledge. RTCA DO 260C costs $800 as a pdf, and TSO-C166c does not mention how an on-ground signal is actually generated.

Some systems detect motion or altitude but that's to turn off the whole transponder, not to signal "on-ground" as it's referred to.

The Garmin GTX330 ES transponder itself does have a squat switch input, and that sets the on-ground status, says Garmin.

The Garmin G3X Touch does have a discrete input for a squat switch, but it's not clear if that can be forwarded to an ADS-B out system. Unikely for an add-on UAT box., IMHO.
 
DO-260 doesn't require a specific method for on-the-ground determination. As Matt rightly pointed out, there are a variety of allowable methods.

Fitz, are the alerts are being generated from *all* aircraft on the ground, or just specific N-numbers? I've seen a couple of alerts from aircraft on the ground at the home 'drome, but that's also happened before 9.22 and could easily be caused by an incorrectly-configured ADS-B Out device.

I understand the possible issue with distraction, but I can also envision a case where an alert from an aircraft on the ground would be a good thing - like at night, when runway/taxiway and aircraft lighting might be confused. There's no such thing as a free lunch...

Dave
 
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Here's what I've found so far (and neither AC 90-114B nor AC 20-172B seemed to mention anything about on-ground determination):

AC 20-165B, “Airworthiness Approval of Automatic Dependent Surveillance - Broadcast OUT Systems,” says:
3.10.2 Air-Ground Status. For aircraft with retractable landing gear, the air-ground status determination is typically provided through a landing gear weight-on-wheels (WOW) switch. For aircraft that have fixed gear, the ADS-B system must still be able to determine the air-ground status of the aircraft. Installations that provide a means to automatically determine air-ground status based on inputs from other aircraft sensors may be acceptable if they can be demonstrated to accurately detect the status. For example, air-ground status may be derived from WOW switch and GPS velocity; or GPS velocity, an airport database, and geometric altitude; or GPS velocity and airspeed. These algorithms should be tested and validated during the installation approval.
Note 1: We recommend that any automatic air-ground determination be more robust than just a simple comparison of ground speed to a single threshold value. Field experience has shown that this method can lead to false air-ground status.
Note 2: Manual selection of the air-ground status is not acceptable.
Page 34: Mode S Transponder Inhibit. …details when the airplane is on the ground.
 
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Thermos said:
Fitz, are the alerts are being generated from *all* aircraft on the ground, or just specific N-numbers?
Click to expand...

As far as I can tell all traffic gnd or not is generating verbose aural alerts, and they are pretty darn distracting especially in the pattern. If I could just get a simple "Traffic" alert like before it would be great, but the 15 word descriptive had to go, especially close to the ground.

Fitz
 
Ed_Wischmeyer said:
I'm trying to find detailed information on ADS-B to fill in my knowledge. RTCA DO 260C costs $800 as a pdf, and TSO-C166c does not mention how an on-ground signal is actually generated.

Some systems detect motion or altitude but that's to turn off the whole transponder, not to signal "on-ground" as it's referred to.

The Garmin GTX330 ES transponder itself does have a squat switch input, and that sets the on-ground status, says Garmin.

The Garmin G3X Touch does have a discrete input for a squat switch, but it's not clear if that can be forwarded to an ADS-B out system. Unikely for an add-on UAT box., IMHO.
Click to expand...

It really depends upon how integrated the two systems are. Both my GRT and G3X have fully integrated transponders (a trig and a 23ES, respectively) and in both cases, they switch from GRD to ALT when the speed goes above a set threshhold; unsure if it is IAS or GS. They do NOT switch on/off or stby/alt based upon speed or motion. One of the goals of ADSB was to improve ATC ground handling at Bravo airports, though I don't believe any of it has been implemented yet. This is why there are paramenters like wingspan, length and antenna offset. This level of detail is irrelevant for separating planes moving at 500 knots, but very meaningful when trying to squeeze two 777's past each other on parallel taxiways.
 
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Alert

I was number 3 today at KCRG and only received the long alert when I was on a 1/2 mile final with another plane taking his time to turn off. Tower easily talked over the alert. I’ve got my volume at 40% for the alerts. It would help if it was shorter but probably worth the aggravation. Hopefully they will shorten the alert, doesn’t need to be that long after all I still have eyes.
 
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