This flight went without a hitch. It's nice to have one of those now and again.
The NSTAR crew began arriving around 7am. There was some extensive mid-level cloud cover at sunrise, but that was pulling away and leaving almost clear skies for us. Temperatures were in the low 60s and just the barest hint of a breeze. We were planning our launch time to coincide with the 2003 Great Plains Super Launch, happening in east-central Colorado that morning. We had prepared for a digipeater experiment between NSTAR and the EOSS balloon, but due to a slow leak in the EOSS balloon, they had to cut their mission short.
We start filling the balloon and do our now-standard check for holes - none this time. This was the replacement 1200g balloon for the one with a hole in it we tried to use for 03-A. We empty the T-tank into the balloon this time, too. All the payloads are working fine and we hook them up to the parachute and load line. Doug KA0O reads off our new NSTAR pre-flight checklist which ensures we don't forget anything like opening the still camera's shutter. The checklist has items like getting a free lift estimate, but the scale won't cooperate with us - no reading at all.
We're ready to go on time, so we release the balloon just before 0747 CDT. Within 30 seconds we know we have a good ascent rate of over 800 ft/min, and within about three minutes it settles into its steady-state ascent rate of around 1000 ft/min.
The balloon remains within sight for us for better than an hour. Shortly after 9am Wayne KE6DZD remarks "I think the balloon burst - it just faded out". My first thought is "nah, that can't be - it's barely over 80,000 ft and we have about 15 minutes to go". Then the alarm on my computer goes off indicated I've received the "burst" notice from the payload. Our maximum altitude is 81,069 ft which occurred at 0907 CDT (1407 UTC).
|Stations heard on the simplex repeater
We get in our vehicles and head to the intersection of US 6 and US 59, about 8 miles away. Telemetry indicates a good chute for the payload, and everything is still operating. A while later, the payload passes overhead at about 22,000 ft and I can just see the parachute for 20 seconds or so - then I take my eyes off it and lose it in the sun. We move two miles farther south on US 59 and stop again to debate our next move. The payload is still moving south at about 20-30 mph and is a couple of miles to our east. We decide to head east on a county road for a mile, then south. We end up coming to a T with Hwy 92 when the balloon is still at 5000 ft or so. Since we can't chase any farther south by road, we get out and watch the terminal descent.
We can see a lot of the balloon hanging from the top of the parachute. This is causing a slow rotation of the stack at a rate of once per every 4-6 seconds, then something will shift and it stabilizes for a short time. During the rotation, the stack is pulled about 30-45 degrees off a vertical axis. The stack floats over Hwy 92 at about 1000 ft AGL and lands in a soybean field within our sight south of the road.
Several of us head the relatively short distance into the field to recover the payload. Everything is undamaged and the parachute is normal. About half of our 1200g balloon came back - normally the Kaysams shred more cleanly. After bringing the payloads back to the vehicles, we review the videotape. Because the landing occurred almost exactly two hours after launch (at 14:47:30 UTC) we were hoping to have videotape of the landing, but the tape ran out at 14:46:18, or 1 minute 12 seconds earlier. Prior to launch, we were not expecting to have tape of the landing because the balloon should have burst at about 98,000 ft. With the early burst, we thought we had a chance.
The FindU logs indicated the backup beacon was nearly perfect. We lost several packets during the turbulence after burst, which is not unexpected. FindU also indicated the backup beacon was picked up by the CLRMRE digipeater near Tulsa, a distance of 343.6 statute miles at the time.
Launch and landing video (about 4 min in length)
Payload view of launch, burst, and near landing (about 9 minutes)
Windows Media (23 Mbytes)
Excel spreadsheet data (450 kbytes)