ADS-B and nearly a near miss

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Rich
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ADS-B and nearly a near miss

Post by Rich »

Yesterday we (wifey and I) departed Prineville and flew over toward the West on a morning excursion to nowhere. A complication flying around here is there is a lot of flight training out of Bend and Redmond plus a confluence of Victor airways and T-routes at Deschutes VOR. Plenty of targets for the fish-finder. We come to a point where we're approaching crossing V25/T261 at a 90 degree angle and see on both Foreflight iPads a plane (signaling via 1090ES) approaching down that path from off to our right. Eventually the plane becomes visible and if we both continued on I might have passed right over him by 50 ft. or less. So I do a climbing right turn and watch him go by on my left- some model of RV, I believe. No action on his part indicated he ever saw us (or didn't care? :shock: ). We continued on with the flight, flying South for awhile and then East, etc. My wife notices that this same plane has continued on down the airway and overtook another, slower plane also along the airway and shot under him by about 800 ft.

On this flight I played a bit with Foreflight's new trick of showing traffic in the AHARS synthetic vision view and what they call "glance", rotating the view through 360 horizontal degrees to look to the sides and behind. Cool trick. Targets show as diamonds positioned relative to your flight path and depict distance and relative altitude. The diamonds get larger as they get closer.

Arriving back over Prineville we see and hear a fairly common complication at the airport. There is a very active flight training program based out of Redmond training scores of young Chinese men for careers in aviation in China. They use the surrounding airports (including Prineville) for some of their training. The real complication is the unfamiliarity most of them have with English, coupled with the fact that lots of them are low-time students, making typical student-pilot mistakes. (The good news is Hillsboro Aviation has outfitted all their planes with 1090-ES.) Three of these planes are just arriving at Prineville, as shown on FF, but their radio transmissions I think I hear don't always line up with the flight paths I observe. So we lurk around at 7,000 ft., South of the airport, watching electronically, visually, and audibly to discern what they're doing. Of course we also have to concern ourselves with other possible traffic that might come by. Finally, it's clear they're doing T&G's in a normal pattern so we can descend and land.

Because that first plane I discussed never reacted to my presence I wondered whether my Transponder as broadcasting the 1090ES as it should. So when I got back I went to the ADS-B performance report site (https://adsbperformance.faa.gov/PAPRRequest.aspx) to check. All came back OK. So the lack of reaction is something of a mystery. It is possible that the plane was IFR and reluctant to deviate from his clearance, but still.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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Tim H
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Re: ADS-B and nearly a near miss

Post by Tim H »

I was reluctant to install ADS-B until last fall when I was acting as safety pilot for night instrument approaches. I could see another airplane in the distance but could not judge how far away it was. We altered our course, but the other plane turned into us. He must not have seen us. It was a close call. After that I got more serious about getting ADS-B.

Shortly after the installation, as I was departing my home field to the north, another airplane reported that he was transitioning the area from east to west and over a landmark that was to our west. Thinking he was already to our west, I wasn’t too concerned. Just to be sure, I gave a quick look to the right (at the same time I got a “TRAFFIC” warning) and sure enough there he was. I like to think I would have seen him, but the ADS-B was a life saver.

Coming back from OSH under the Chicago Class B, approach called traffic “opposite direction, same altitude, less than 3 miles”. I dropped down 200 feet, and got another traffic alert from Chicago approach, “opposite direction, less than 1 mile”. Just as I saw him, I got a “TRAFFIC” warning from ADS-B.

Having said that, it’s easy to fixate on the ADS-B and not look outside. I’ve also looked down and seen an airplane underneath me that did not show up on ADS-B which was a good reminder to “look outside and peek inside”.
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Rich
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Re: ADS-B and nearly a near miss

Post by Rich »

Of course, you always have to allow for the planes that none of the electronic traffic detection approaches will detect. And recognize that Mode A/C traffic has significant delays in position updates, as well as being prone to dropping and reappearing in your display.

FF is just one additional instrument included in my scan, as it sits right below the six-pack and is easily included without fixating.
2002 DA40-180: MT, PowerFlow, 530W/430W, KAP140, ext. baggage, 1090 ES out, 2646 MTOW, 40gal., Surefly, Flightstream 210, Orion 600 LED, XeVision, Aspen E5
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