Hey, ADS-B Actually Works!

Jay Honeck

Touchdown! Greaser!
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Jun 6, 2008
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Ingleside, TX
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Jay Honeck
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KTFP - Ingleside, TX
So Wednesday we were flying into Texas Gulf Coast Regional Airport (KLBX) for dinner at the Crosswinds Cafe, when we had a relatively close call with a Cirrus driver. Here's the tale:

First, let me 'splain that we've got the RV-8A's back cockpit set up with a Nexus 7 tablet Bluetoothed to the Garmin GDL-39 ADS-B receiver. This is a great set up, giving us a moving map sectional on an HD screen, with traffic and weather overlaid.

As we fly it, this RIO position has primary responsibility for chart awareness, radio frequencies, tank change timing, etc., which leaves the PIC free to fly the plane and work the radios. Since we trade off PIC time, we're both well-versed in this somewhat unique version of cockpit resource management.

On this leg, I was the RIO (or GIB, if you prefer), while Mary was PIC. The wind, as usual, was out of the South, and RWY 18 is right hand traffic at KLBX, so Mary was setting up her approach to match. We were arriving from the West-Southwest, so we were entering on a natural 45 degree to downwind.

As we're sliding down from our cruising altitude of 7500', I'm watching the ADS-B traffic as it's overlaid on the sectional screen. There are, of course, a bunch of targets North of KLBX -- that's Houston's busy airspace. Even with the altitude filters on, there were too many targets to track.

But no worries -- the area near KLBX was clear. Except for one little triangle that was moseying our way...

I'm casually watching this target, not wanting to say much to disturb my favorite PIC. ADS-B traffic has been so sporadic as to be mostly meaningless, so we have not gotten into the habit of using it for traffic avoidance. Still, this one little triangle appeared to be heading right for us...so I mentioned something on the intercom.

Mary acknowledged, and continued downhill. At this point we heard a Cirrus announce that they were "x miles North, inbound, low approach only". Hmmm...okay. How far out was that again? Neither of us had heard.

Still, I had that one target on the screen. It was coming right at us, so I mentioned it again as she entered downwind.

Now, Mary's getting ready to land. Boost pump on, prop full forward, mixture rich. Landing lights on. Speed below 100, drop half flaps.

Still, no plane in sight. No one is announcing on the radio. The target is still out there. Mary drops full flaps, and turns to base...

I'm looking at the screen, which I've now zoomed in. There's the target, and it's right...THERE. I look out the canopy, and sure enough, low and to our left is the guy on final, on a collision course with us. He never said a word, despite Mary's continual announcements as she coursed around the landing circuit.

I gently but firmly told Mary to add power, pull up and break left. Without questioning, she did, and we missed the guy by a mile. It wasn't even a close call -- but would we EVER have seen him without ADS-B?

Without my watching that target grow ever closer, I would not have known to look out the window in that exact direction. Mary never saw him, as she was fixated on the runway. Would she have turned her head to the left (as is our usual practice) in time to avoid a collision, were it not for my timely warning?

I don't know. I'd like to think that we would have seen Mr. Cirrus without ADS-B, but who knows? All I know is that this was the very first instance of ADS-B traffic actually playing a role with us in-flight -- and it was very, VERY nice to have!
 
Was the Cirrus broadcasting ADSB out to give you a picture? Perhaps a 1090ES transponder to allow the Garmin to plot his position?

Or was the Garmin getting the picture from a rebroadcast from FAA?
Which means someone within 15 miles of you had ADSB out.
in that area it is very likely

ADSB is great, the Garmin and Stratus and Dual units are great, but have limitations.
Not all traffic will show up.

Shame on the other pilot for not making more announcements.
 
Hopefully you were calling runway 17, not 18 lol. Small world though, I flew with my CFI to Galveston to solo at a towered airport on Wednesday. You must really like that restaurant, I still haven't tried it out yet.
 
Was the Cirrus broadcasting ADSB out to give you a picture? Perhaps a 1090ES transponder to allow the Garmin to plot his position?

Or was the Garmin getting the picture from a rebroadcast from FAA?
Which means someone within 15 miles of you had ADSB out.
in that area it is very likely

ADSB is great, the Garmin and Stratus and Dual units are great, but have limitations.
Not all traffic will show up.

Shame on the other pilot for not making more announcements.

I'm assuming the info was from a ground station. I was close enough to Houston for lots of heavy metal pilots to be around, triggering the ground stations to broadcast their traffic info.

You know -- like they should be doing ALL THE TIME. :mad2:

But that's a different topic entirely. I was just glad to see the system finally working as advertised. Who knows, it may have saved our lives that day?
 
Hopefully you were calling runway 17, not 18 lol. Small world though, I flew with my CFI to Galveston to solo at a towered airport on Wednesday. You must really like that restaurant, I still haven't tried it out yet.

Hey, I was the RIO. I don't have to know the stinking runway number! :lol:

But, yeah, that restaurant is great. It's a perfect flight for us, from here -- just long enough to make it feel like we've gone somewhere. And Amelia usually gathers a crowd on the ramp, giving us the opportunity to hand out hotel propaganda...
 
My lights are usually on during the descent and within 10 miles of my destination. The other guy may have been on the wrong freq...been there twice so far. I was wondering why nobody was talking. Figured it out on downwind. Now I always watch people like me.
 
That "Skyguard" transmitter has piqued my interest. Surprised it's legal...

I've got a 480, and the way things are looking, Garmin will probably release the ADS-B position source software upgrade on New Year's Eve, 2019!!
 
That "Skyguard" transmitter has piqued my interest. Surprised it's legal...

Why are you surprised it is legal? I was more surprised to see others charging big dollars for technology that has been around and mass produced for decades. If you don't believe it is legal, enter the string R83 into the grantee code field of the following web page and click the search button. Then under the only row for SkyGuardTWX that appears in the result page, click on the word Detail. You should see 11 exhibits in that result page. Open the FCC letter to read the grant of certification.

http://transition.fcc.gov/oet/ea/fccid/

So while the FCC allows its use, it is not yet certified to the FAA TSO specs. It is my understanding that meeting TSO specs doesn't become required till the year 2020, so no problem there. I think there is a code field in the transmissions that indicates whether the equipment is non-TSOed, but I may be mis-remembering.
 
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