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Category: 2004
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Our first attempt to launch NSTAR 04-A came on February 22. We joined up at Gretna Middle School about 8am for a 9am launch. Unfortunately, our balloon got away from us before we could tie it off and without enough helium for a second attempt, we had to scrub the launch for the day.  See this PG-rated clip for the results.

As we made our way to the launch site for our second attempt, on Saturday, February 28th, I wasn’t sure we’d be successful on this day either. While driving through Treynor, about 4 miles from the launch site, we noticed the flags snapping in about a 15-mph breeze. It is fairly risky trying to launch a balloon in such conditions, as the wind can blow the balloon into surrounding objects or the ground itself while filling or soon thereafter.

To my relief, as we got out of the car at Scott’s, the wind was nearly calm. Scott’s farm is at a lower elevation and with the morning inversion, the higher winds were restricted to a layer off the ground. Treynor itself is on a ridge top and was in the layer of higher winds. We unload the car and start preparing to fill the balloon.

As a result of our first attempt of the year, we obtained some quick-release hose clamps to keep the balloon securely on the fill tube. These worked very well for us and we filled the balloon without incident. Also, we released the lanyards while hanging onto the payloads to reduce the risk of the lanyards fouling. This also worked well and we released the balloon at 1342 UTC.

Soon after launch, when the balloon was still less than a mile away, we got our first SSTV picture. The signal was weak and noisy, barely enough to decode. During the preparation, I decided to put our "questionable" equipment on the SSTV payload. This would help to determine which radio and antenna were bad. The SSTV’s radio was the VX-1R that fell 13 miles back in 2001 – it’ll be retired now. The antenna has some teeth marks from one of our cats and will be taken out of service as well.

The other payloads are working well, including the backup beacon that had been troubling us for quite a few flights. We chase east on US 6 and then north on US 59 to I-80. Our projected landing site was a few miles south of Jefferson IA, so our plan was to wait north of Guthrie Center until the burst and go from there. As we got north of Guthrie Center, we made contact with Larry N0BKB who was waiting at the intersection of 25 and 141. We pulled in behind him and waited on the burst.

Above 40,000 ft, the balloon’s ascent rate decreased from about 1000 ft/min to less than 600. Since the winds were light at those altitudes, it didn’t have much of an effect on the landing prediction. However, our 1500g Kaysam balloon gave up earlier than expected, at 1533 UTC and an altitude of 92,913 feet.

Since the actual burst location was near the predicted burst location, we expected the landing to be north and east from the intersection of 25 and 141. We headed closer to the predicted landing site, but it soon became apparent that it was not going to go quite that far. We backtracked to the west and south in an attempt to be close to the landing when it happened. We were within about a half-mile, but I could not see the payload stack against the high overcast. The rest of the Des Moines-based chase team all converged on the same area and some of them reported seeing the payload. Landing occurred at 1606 UTC about 3 miles NE of Bayard IA.

We had a 3/8-mi walk into the field to retrieve the payloads. Fortunately, it was near enough to a fence line that we could walk on the somewhat-frozen snow drifts most of the way there. The payloads landed in some mud but were undamaged. After recovery, the chase team had lunch at a nice pizza place in Guthrie Center before heading home.

The still pictures turned out reasonably well. The ISO 200 film did not allow for a fast enough shutter speed to stop the payload’s rotation and swinging all the time. But several did turn out well. The camcorder video taped to a few minutes after burst, and showed that the payloads may have nearly turned upside down in the post-burst chaos. However, they did stabilize within about 20 seconds or so. The EEPROM log was still using the settings I had for our short 03-F flight, so the detailed logging ran out of memory at about 78,000 ft.

Thanks to a couple of contributors who made donations to help keep NSTAR flying!