As we reported in our last post, we were ready to launch two balloons last Saturday, August 27th. After completing the Board and getting ready for launch, Michael started testing the tracker and discovered it wasn’t working properly. The night before, we discovered our tracker was only transmitting one packet. We need both packets sent two minutes apart to receive the 6 Grid Maidenhead location, altitude and other data. Not having all the data we needed for a successful launch, we decided to scrub the launch until we could find the trouble.
On our last post we had shown our 3rd party manufactured tracker minus a few chips. Because of the chip shortage, it’s necessary for us to add some our own sourced chips. After spending time looking at the software as a possible issue, we suspected the problem to be a hardware issue. One of the substituted chips was the MS5351 Clock Generator. On our previous trackers, we were using the Skyworks Si5351, however, due to supply chain issues, we ordered the MS5351, thinking it was a plug-in replacement for the Skyworks chip. We found that the MS5351’s didn’t always work. After finding a board that failed consistently, we removed the MS5351 and replaced it with an original Skyworks chip, we retested, and we’re now back in business. We now have two working trackers for our next launch. We also ordered the Skyworks Si5351A-B-GT chips from Digikey to make sure our future trackers will work properly.
We also discovered during this down period, that the two Yokohama balloons that were prepared for last Saturday, were found to be leaking a small amount of gas – about 1g of lift per day. We were planning on using these pre-stretched and filled with the proper free lift gas for this Saturday’s launch. I suppose it was pure luck to discover the balloons had a small leak which would have lead to a failed launch, if we hadn’t scrubbed the launch.
After we discovered these failed balloons, Michael AA6DY and Stewart KB9LM of our Technical team had conference calls with Ken Daniel K9YO and with Tom Medlin W5KUB on our different balloons. Ken has been successful flying the SAG balloons and Tom, the Yokohama’s. While Stewart was able to get the process of pre-stretching and sealing from Ken, Tom shared that the failure rate of a Yokohama balloon was about 70%. While we’re not sure if that’s a failure from launch or cutting short the journey, Tom’s flight 112 has just circumnavigated the world and is currently flying on day 82 with a Yokohama balloon over Canada heading to the north pole.
We have several groups working together to prepare for a launch. After the Balloons, Tracker, Solar Panels and Antenna package are prepared, the last step before launch is to look at the weather and the Jetstream. It is now up to our Meteorological committee to determine whether we are good to go, which we now have.
Our Meteorological committee of Kelsi Mulley KE9LSI (our new General) and her Dad Doug Mulley KD9TPM are providing daily weather reports leading up to the launch. NOAA (National Oceanic and Athmospheric Administration) provides all our models from balloon location for all weather and trajectory. NOAA gives us updates on Hurricanes and Cyclones which may impact our launch as well as a Hysplit trajectory, which shows our projection of travel from a given altitude and location. We start with our launch location and projected altitude and create a model showing the projected path over a 48 or 84 hour period. The NOAA Hysplit Trajectory model takes into account the weather, pressure, and Jetstream, and adjusts the altitude and direction. During the flight this committee will update the Hysplit models.
We are now planning our next launch on Saturday September 3rd 2022 at Willow Hill Golf Course, 1350 Willow Rd. in Northbrook, IL. We will be launching two balloons, KD9UQB for Jim Janiak, and AA6DY for Michael Seedman, and now with the Go Ahead from our committee, we will be meeting at 8:30 am Saturday September 3rd.
So, what do we have in common with Artemis? We research, prepare and test, up to and throughout our launch.
