NSTAR Flight 12-B was for one of our favorite customers – the Aerospace Education Workshop at UNO. Paul KD4STH had his usual BalloonSat workshop on Friday, and Saturday was the day to put them in the air.
Because of the expected track to the south, we chose the ballfield parking lot in Weeping Water as our launch site. With light winds and protection from the surrounding terrain, we had almost ideal conditions for filling and launching our 1200g Hwoyee balloon. However, during final payload checkout I noticed that our backup beacon had stopped functioning. The switching regulator that provides 5V to the TinyTrak 3 and the GPS was very warm, so I suspected a short on the 5V supply on the TinyTrak – this had happened before due to the ground and 5V wires getting twisted and shorting out. Our main beacon (a BigRedBee GPS/APRS combo) was working fine and performed without a hitch on its maiden flight in March, so we pressed ahead and launched at 0810 CDT (1310 UTC).
Our flight prediction had the landing west of Tecumseh, so we drove there and set up shop in the Casey's parking lot to watch the flights progress. With practically clear skies we could see the balloon approaching us from the north before turning to the west as the winds shifted above 50,000 ft. Our ascent rate was slower than expected, averaging only 750 ft/min.
With the burst expected not too far west of Tecumseh, our plan was to wait there until the balloon burst. As the balloon passed 100,000 ft, it continued to drift farther and farther away from us to the west. Expecting burst almost any minute, we waited and waited for it to pop. Our last UNO flight in 2011 was a record-setting 112,949 feet but with a smaller balloon and a fairly heavy load we did not expect to match that altitude. However, it lasted 25 minutes longer and 16,000 ft higher than expected, finally giving up at 116,789 feet at 1045 CDT (1545 UTC) and is now NSTAR's present altitude record. A picture snapped just before burst is also our highest photo on record.
Photo from NSTAR 12-B at 116,789 feet
By this time the balloon was 10 miles or so northwest of Beatrice, and we now had a 40-some mile drive to the landing. This meant it was unlikely we could be there in time for the landing, but we gave it our best. As we came out the west side of Beatrice, the payloads landed about 10 miles away northwest of the town of Harbine at 1128 CDT (1628 UTC). As we drove up, a position report was received from the payloads on the ground. This was a good sign because (1) we were still 2-3 miles away so that meant the BigRedBee's signal was a good one even with the payloads lying on the ground, and (2) it would simplify our search greatly.
Thanks to the wonders of 4G coverage, we were able to do some Google Earth recon as we drove up. We were in an area of cornfields, but from the satellite image we could not tell for sure if we were in corn or possibly some grass. Without any farmhouses in the area, we could not tell who owned the land where our payloads were. Even though there was a vehicle path back into the field, we chose to park on the road and head back on foot.
We had some good luck again as the payloads were in some grass along a dry creek bed. We could see the parachute from about 100 yards away and walked right up to it. After getting some pictures, we picked everything up and headed back to the vehicles for the long drive home.