So, last weekend I took the C up for a two hour refamiliarization flight and to do a little sightseeing over some of the areas here in the Florida panhandle that were devastated last October by Hurricane Michael. The entirety of the flight was conducted VFR at 3,000’ MSL and in Class E airspace while monitoring the various Approach sectors but not receiving radar advisories.
About a year ago I had a fellow MooneySpace member put together a Stratux unit for me that I gave to my dad as a gift. He never used it, though, and he gave it back to me not too long ago, so I decided on this flight to give it a try with the free VFR version of WingX, which I downloaded to my iPad specifically for this purpose. I used WingX for about five years back before portable ADS-B “in” units were readily available, but for the past several years I have been flying with Garmin Pilot and a GDL39-3D for ADS-B “in”. But that’s not that relevant to this story, I guess, except that I was surprised to see how little WingX had changed. Suffice it to say that the Stratux seemed to perform well, with full weather, traffic, and AHRS functionalities.
A few minutes into the flight Tallahassee Approach called me out as unidentified traffic at 3,000’ to another airplane that I was already watching on WingX via the Stratux, so I know my transponder and encoder were also working and reporting accurately. Maybe 30 minutes later, though, I noticed that rather than blinking when interrogated as is usually the case the reply light on my transponder was steadily on all of the time. I assume it had been that way for the entirety of the flight, but I just hadn’t noticed it until then. I tried recycling the transponder a couple of times but that didn’t change anything. I knew for a fact that the reply light had functioned normally on my flight previous to this one and, honestly, the transponder and encoder are both relatively new and have been very reliable and have tested ok, so I just didn’t believe anything was wrong with them. So I starting thinking about what had changed since my last flight that could be causing the reply light to stay on all of the time and the only thing I could think of was the Stratux’s WiFI network, so I turned it off and, voila, the transponder’s reply light started blinking normally when interrogated.. I turned the WiFi and the Stratux back on one more time just to verify the correlation but needless to say, thereafter, they were turned off for the remainder of the flight.
Can anyone explain what might have been going on here? I have flown with this iPad many, many times using Garmin Pilot and connecting to the GDL39-3D via Bluetooth without observing these issues, but I have never used this iPad’s WiFi network in flight and I have obviously never used the Stratux before.