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Category: 2004
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Our second launch of the year was at the Central Plains Severe Weather Symposium in Lincoln. Wayne, Doug, and I arrived shortly after 8am to check out the launch area surroundings. Eventually we found a spot south of the auditorium that was well-shielded from the 20-30 mph winds blowing that morning. I gave a 45-minute presentation on NSTAR at 9:30, then started launch preparation about 10:30.

With the wind blocked by the building, we started filling about 10:45 and didn’t have much trouble with the wind during the fill. About the time we got the payloads tied on, much of the crowd came out to watch our launch. We did a quick check with the Lincoln tower to make sure we were clear, and released the balloon at 1112 CST before an audience of about 100.

A swirl in the wind abruptly carried the balloon towards the west-facing wall of the school, and the bottom payload carrying our backup beacon struck the side and then the roof. Later we determined that this silenced the backup beacon by causing the battery compartment on the radio to open and disconnect the power. We’ll mitigate this next time with some tape. Otherwise, the payload was undamaged.

Soon after launch, we got our first SSTV picture with good clarity, so it appeared we had mostly fixed our earlier problems with slow-scan. We packed our equipment and headed out on our chase by 1120.

It seemed to take forever just to get out of Lincoln. Next time I’ll do a little more research on the fastest way out of town. We went east on Havelock and then south on 84th, seemingly hitting every red light along the way. Finally we got onto Hwy 2 and headed towards Nebraska City. As we were coming up on Syracuse, the capsule reported the balloon had burst at 62,405 ft at 1806 UTC (1206 CST).

We continued on across the Missouri River, occasionally getting SSTV pictures. Some of them had regular dropouts, indicating the payloads were spiraling down as they fell. But the descent rates were reasonable, so we weren’t too concerned with a fouled chute. About the time we got onto I-29 to head south, we got a last report at 2300 ft MSL (1200 ft AGL) south of Fairfax MO. Landing occurred at 1835 UTC (1235 CST) about 4 miles SSE of Fairfax.

It took us about 45 minutes more to get to the landing site. In the meantime, Mike N0GGU had made his way from his QTH near Graham. He called me on my cell phone to report that he was near the payloads and that they were safe. We arrived about 1315 and retrieved the payloads.

The still camera worked well. An improved algorithm to detect bad GPS data prevented any unplanned triggering of the camera, which on past missions had caused "extra" pictures to be taken. The SSTV camera worked better than on previous flights, but still had fairly weak signals. Given that the antenna was just an 8" whip, I suppose that’s to be expected. We may try a J-pole antenna on a future flight.

The video quality was also pretty good. We had a lot of rotation early on, which appeared to be induced by the backup beacon payload striking the school. Within a few minutes, most of that had stabilized. On the way down, the payloads got into a spiral that continued most of the way down. About 10,000 ft the stack stabilized into a nearly-vertical configuration for a few minutes, then began to spiral again a few minutes later. After landing, the wind caught the parachute and dragged the payloads towards a fence line for about 10-20 ft.

Paul Verhage's flight on Sunday the 21st went well too, with the landing 8 miles N of Chillicothe MO.