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Category: 2002
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NSTAR 02-B had a successful flight on Saturday, March 30th from the Central Plains Severe Weather Symposium in Lincoln.  The NWS office in Valley NE contributed two balloons to help support our flight.

Most of the launch crew arrived between 7:30 and 8am in order to get parking spaces near the launch site in front of the conference center. I gave a presentation on NSTAR from 9 to 9:45, then we started the equipment setup outside.

About 10:35am we started to fill the balloon. This all went normally, and I noticed that the Kaymont "severe-weather" balloon was more round than teardrop-shaped after inflation. As we put the lanyards through the ring, I noticed that the heat shrink that I had around the knots on one of them had come off and the string was rather frayed. No matter, I thought, I'll fix it later if I get a chance.

The previous presentation ended at 10:45 and the crowd came out to watch the launch. Probably had a couple of hundred on hand. We winch the balloon out into position, check in with Lincoln Tower, do our countdown from five, then Wayne KE6DZD upends the crescent wrench holding the lanyards and away it goes.

For about fifteen feet. The lanyard snags on the ring - looks like a rat's nest up there. Nuts. Doug KA0O suggests cutting the lanyard away, but I give it a good tug to see if I can clear it (as if Doug's pulling wasn't good enough).

Suddenly the payload comes screaming earthward - the chute billows open and it all lands in front of the gasping crowd. My reaction, hopefully unvoiced, was "what the...?" The balloon is still caught on the lanyards, but I figure it will slowly unravel itself and go free all by itself shortly.

I can see a length of string dangling from the balloon - initially I thought that was the load line and that it had snapped near the clip ring I use to attach to the top of the chute. I check the chute and a full length of load line is still there, so then I surmised it was sawed in two by the lanyards near the balloon neck.

Meanwhile we're carefully reeling the balloon back in, expecting it to go any time, most likely just before we can secure it. We catch a break, however, as I was able to get the free end of the lanyard and we get the balloon back. We attach the load line directly to the ring, then let the balloon out by the load line rather than risk a lanyard fouling again. So after a few more minutes and a check to make sure the payloads are still functioning, we have our second launch of the day at 10:56am with the same balloon.

The chase team piles into their vehicles and off we go towards Nebraska City. Lots of contacts heard on the simplex repeater - it's working much better than the previous flight. I have my D7 in the car with me tuned to the backup beacon and the laptop is monitoring the primary. Both are going fine.

We knew ahead of time we were unlikely to be near the balloon at landing. Fortunately, Larry N0BKB, Mike N0GGU, and Steve N0ORU are already in Bedford, and Don KA0JLF, Cris N0XZB, and Bob K0FPC are heading north from St Joseph. Burst is at 78,760 ft, but the capsule APRS bulletin had it at 78,482 ft. Need to check the programming on this.

Landing was at 12:54pm (1854 UTC) between Clearfield and Diagonal IA in a plowed cornfield about 200 yds from the road. Again, no powerlines nearby, but if it had drifted downwind a bit farther it might have gotten caught in a copse of trees. All the payloads worked after the landing and nothing was broken. The chase teams headed for Corning for a pizza lunch.

The videotape shows that the VHF backup beacon caused a burp in the video recording every 30 seconds when it transmitted. This was probably due to the higher power and the antenna's proximity to the camcorder (it was directly above it and probably had a lot of radiation off the coax shield etc.).

Launch date/time:

23 Feb 2002 1656 UTC (1056 CST)

Launch site:

Nebraska Center for Continuing Education 
University of Nebraska-Lincoln East Campus
Lincoln, NE

Payload frequencies:

Primary - 144.390 MHz (national APRS frequency)
Callsign N9XTN-11
Backup  - 147.585 MHz call N9XTN-12
Voice   - 446.30 MHz simplex repeater

Telemetry:

AX.25 APRS-formatted location and telemetry,
other raw text

Envelope:

800g Kaymont "severe-weather" balloon

Maximum altitude:

78,760 ft

Payload weights:

5.0 lbs main capsule
5.5 lbs secondary capsule

Helium used:

250 cu ft (approx.)

Flight duration:

1 hour 56 minutes

 

 

Equipment manifest

 

 

Basic Stamp 2p microcontroller
Kantronics KPC-3 v6.0 TNC (modem)
Alinco DJ-190T 2m handheld radio
Garmin GPS-35LVS GPS unit
12" dual-band whip antenna
Custom 7.2V 4000 mAh battery pack

2 - Yaesu VX-1R dual-band mini handheld
radios w/12" whip antennas
2 - custom 7.2V 2700 mAh packs
Radio Shack simplex repeater
JVC GR-AX220U VHS-C camcorder
Motorola Oncore M12 GPS
Synergy Systems GPS mini-antenna

Callsigns heard on the simplex repeater

WD0BFO WE0C N0HPP KC0KXR WD0EGK
N9XTN N0AJI KB0QKH KC0KHA N0RHL
K0SM K0NG KA0JLF K0IH KE6DZD
N0UQZ KC0HWG N0YUE WA0ZQG N0BKB
KC0JGW KA0O KC0HMI K0FPC N0ORU