Our first flight of the year was on a clear and cool February morning, with a few cirrus clouds beginning to come overhead. As we drove out to the launch site, several locations with flags flying indicated to us there might be a little breeze to contend with. We arrived at the launch site around 0800 and began unpacking our equipment. Shawn, a newbie to our hobby, graciously brought us some donuts to enjoy. Most of the time the wind was quiet, but a few gusts to around 10 mph came now and again. We began filling the balloon about 0845 and didn’t have much trouble, though. The payloads were all activated and checked out, and the stack was released at 09:07:45 CST.
As we were getting ready to leave, I noticed that the main beacon had ceased transmitting data at about 0922 and 20,000 ft. While I was double-checking my radio settings, I received a call from Ralph W0RPK who said he observed the same thing and that the main beacon’s transmitter had remained on for over two minutes with an unmodulated carrier before shutting off entirely. This was disconcerting, as this would be our second main payload problem in as many flights. I called on the simplex repeater (which was working well) to let everyone know they should track the backup beacon instead. Wayne KE6DZD had the presence of mind to place his TH-D7 on the main beacon’s frequency with the volume up so if it came back we’d know it.We left the launch site and headed east on Hwy 92. The backup beacon and simplex repeater were both working quite well, so I wasn’t too worried about recovery. We had fallen a little behind on the chase, but with a little luck we should be close enough to the landing to ensure a good recovery even if we didn’t hear the beacon after landing. I had expected our 650g Kaysam balloon to burst around 65,000 ft, and it was pretty close to its rated altitude, bursting at 62,067 ft at 9:52:34.
Now it appeared the landing would be just northeast of Massena by two or three miles. As the balloon came down, I estimated we could get to the landing site if we didn’t make any navigation mistakes. As we got near Massena, Wayne’s D7 came to life, indicating the main payload had begun to function again. I switched my tracking radio back to the main beacon and the data looked good. This would make the end of our chase easier, as the main payload reports positions twice a minute and even more frequently during the final two minutes of flight.
Some of the other chase crews reported having the parachute in sight as we approached. We turned north off Hwy 92 and soon found ourselves on a “Service B” minimum-maintenance road – fortunately, a pretty dry one. We met up with some of the other chasers and stopped to watch the payloads pass overhead at about 2000 ft AGL. They landed at 10:25:10 CST about 200 yards off the road in a corn field.
The payloads all functioned after landing and were undamaged. After reviewing the data, it appears the DataTrak PIC (which replaced our KPC-3) may have “frozen”, causing the transmitter to remain on but sending no data. What caused it to resume functioning again later is not known. Over 100 pictures were taken by the digital camera, and some showed evidence of strong RF fields (a herringbone pattern in the image). One potential way to mitigate this is to put the payload antenna on a ground plane – this should also help the digital-camera-to-GPS interference problem observed on the last flight.