Mode 3A is a common failure with the wing tip and tail light units. It has to do with lack of radar coverage. Your transponder isn't getting interrogated by radar when you first take off due to your low altitude being below radar coverage. Since the transponder isn't transmitting anything, the ADS-B unit doesn't pick up the squawk and altitude codes from the transponder. Once the transponder starts replying to radar, you no longer have the error. If you want to get a clean report, fly to an airport that has radar. Spend 30 minutes or so on the ground, then do a test flight staying within 20 miles or so of the site and land back at the same airport. Pull a new report based on the time of the flight and it will be a passing report. Bottom line is, don't worry about the Mode 3A failures. Your unit is working correctly and this is an artifact of your transponder not being queried by radar constantly. Everyone around you will still be seeing you, and it will work just fine any time you are at sufficient altitude to have radar coverage, or if you are in class B or C airspace as there is radar based at those airports.
-Jeff Scott Arkansas Ozarks > Sent: Sunday, June 28, 2020 at 8:44 PM > From: "Flesner via KRnet" <krnet@list.krnet.org> > To: "Flesner via KRnet" <krnet@list.krnet.org> > Cc: "Flesner" <fles...@frontier.com> > Subject: Re: KR> ADS-B out update > > On 6/28/2020 8:18 PM, Flesner via KRnet wrote: > > There was nothing highlighted so I guess it works. > > ++++++++++++++++++++++++++++++++++++++++++++ > > I lied !!! I went back and looked at the report and didn't realize it > was six pages long. Near the bottom there was one box highlighted in > red. It was in the "OTHER" section of the report and the box was > labeled "MODE 3A" and apparently it didn't transmit my four letter code > (1200) for 21 seconds or so. I'm thinking I'll not lose too much sleep > over that. I'm guessing that could have been as I was just acquiring or > loosing radar coverage. I have to get pretty high at my home base to > get coverage. On ILS flights during IMC they hole the number two > aircraft at 3000 feet until the first is on the ground and clear. > Someone more knowledgeable might have a better explanation. > > Larry Flesner > > > _______________________________________________ > Search the KRnet Archives at > https://www.mail-archive.com/krnet@list.krnet.org/. > Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. > see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change > options. > To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org > _______________________________________________ Search the KRnet Archives at https://www.mail-archive.com/krnet@list.krnet.org/. Please see LIST RULES and KRnet info at http://www.krnet.org/info.html. see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options. To UNsubscribe from KRnet, send a message to krnet-le...@list.krnet.org
