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Category: 2008
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The weather leading up to this flight had be excellent for over a week, with every morning calm and clear. Saturday the 20th continued that trend with relatively clear skies and temperatures about 60. As we drove towards Treynor some patchy fog was observed in the valleys.

Our launch site was Scott KC0MTH's farm for the first time in a couple of years. Our sole flight of 2006 was launched from there, which had the backup beacon separate from the rest on descent. None of us recalled this at the time, however.

The winds continued to stay calm through the filling process for our 1200g Kaymont balloon. With just the three of us we decided on a two-man release so Kurt KC0HMI could take pictures and video. Wayne KE6DZD held the balloon and I held the main payload off to the side. The idea was to have the balloon lift the main payload out of my hands relatively softly, then the lighter backup beacon would be lifted off the ground by itself. This worked pretty well since there was no wind – the whole works lifted almost vertically when Wayne let go of the balloon at 0850 CDT (1350 UTC).

 

 NSTAR 08-D at the moment of launch (Photo by Kurt Kettleson KC0HMI)

With a short chase expected, we took our time packing the launch equipment back into the CR-V, which would be left at the launch site while we chased in Wayne's Jeep. We headed east and south to take up a position about 3 miles west of Elliott, near where the landing was forecast. Both beacons and the simplex repeater were functioning OK for the basics. However, the simplex repeater was supposed to make periodic announcements and it was not doing that. I attempted to re-program the repeater from the ground, but could not get the DTMF codes into the repeater well enough to do it. It did work OK for contacts, and we made several during the flight, including one to Roger KC0MWM in Grand Island.

From our location east of Elliot, we were able to see the balloon as it ascended above 70,000 ft. The balloon finally burst at 89,246 ft and 1011 CDT (1511 UTC) about halfway between Elliott and Carson.

As the balloon descended and we monitored the data coming from the main beacon, it occurred to us that we should check the backup beacon since we had not listened to it for quite a while. I pulled out my Kenwood TH-D7 handheld to check for recent positions (it was sitting on the dash monitoring 144.39). The last report from N9XTN-12 was at 45,000 ft, while the -11 reports were still above 70,000 ft. Oh, no, it's probably fallen off again. We continued to monitor while Wayne called his wife on the phone to check for additional I-gated positions that we might not hear. The simplex repeater also did not respond to our transmissions. We heard another report at 17,000 ft, then two more that were fluttering too badly to be decoded. No additional reports were heard by the area I-gates either.

Since there wasn't anything we could do about the backup beacon, we now focused on recovering the main payload. The descent was slower with the weight loss and the payload made a slow clockwise circle to our north. We relocated a couple miles north and west and finally spotted the payloads at about 6000' MSL passing almost overhead. We took a gravel road that paralleled the payload's path north and stopped to grab some video and stills of the landing, which was in a grassy field at 1056 CDT (1556 UTC).

Our hypothesis was that the spring clip we used to attach the backup beacon had opened and released the line – that had happened to us previously. Normally we tape any spring clips shut, but forgot that for this flight.  This time, though, the carry strap had completely ripped off the lunch cooler body. We packed up the payloads and began heading to the last known location of the backup beacon.

Based on the main payload's descent and the fact that the backup beacon was falling much faster, we estimated that the backup beacon had fallen about a half-mile west and a little north of the 17,000 report. This put the payload at least a quarter mile from the nearest road. If it had fallen in a corn or bean field, I figured we'd have no hope of finding it as it could be anywhere within a 200-yard circle of our estimate. There were some hay fields in the area and we had some hope that it could have fallen into one of those - the hay might be short enough to let us see it.

As we approached the area, with our radios tuned to 144.39 with the squelch open, I heard the distinctive sound of the TinyTrak3 packet tones on the radio. I looked at the computer and it had captured a status beacon from the payload! This did not give us a location, but did let us know it was indeed in the area and was still transmitting. I told Wayne to stop the Jeep and we waited for another minute to elapse for the next beacon. Right on schedule, it transmitted again and this time we decoded the position. It was very close to our estimate, and equidistant from the road we were on and the next one to the east. We drove around the corner and began looking for a way to walk into the field. Fortunately we spotted a drivable path back into the field and drove in. When we had to stop, the APRS report said our beacon was about 500 ft off to the west. We put the coordinates into a handheld GPS and walked through the bean field.

The indicated location was right on an erosion control ridge which divided the bean field from an adjacent corn field. The roundoff error with the APRS report was 50 feet, and factoring some GPS error and other fudging figured a box of about 200 feet on a side. Half of the box was in the beans so we searched the easy half first and came up empty. Next I walked on top of the ridge through six-foot-high weeds while Wayne searched the grass at the foot of the ridge and the first two rows of corn on the far side. Wayne spotted the payload just inside the first row of corn, sitting upright on the ground just as if someone had placed it there. The package exterior was undamaged on the outside and the surrounding corn also showed no evidence that it had struck the corn during landing. It's possible it landed in the grass and weeds on the ridge and rolled down into the corn.

Tracks of main beacon (dark blue) and backup beacon (pink).  The location labeled N9XTN-12 was the last airborne location recorded.  The actual landing was west and a little north of this location.
The nylon carry strap ripped free of the package

The contents of the package were also undamaged by their nearly 15-mile fall. The antenna and coax for the simplex repeater were completely missing – the coax appeared to have come unscrewed from the HT and had fallen off. The carry strap was stitched only to the outer layer of the cooler and simply ripped loose. The replacement cooler will be inspected for a more secure attachment.

Click on slideshows below to show larger images

Aerial photos

Ground photos