NSL-3

NSL-3 was an attempt at a very high altitude using a 2kg balloon. Estimates are over 100k' for the altitude based on measurements of time of flight, measured ascent and descent rate, as well as measurements from the image.
Unfortunately the GPS used for that flight was a barometric based and it was in a sealed box, so the measurements were not useful. In addition, the SPOT Tracker stops sending telemetry above about 50k'.

The NSL-3 Balloon launched at 8:55am, Sunday, September 26 at 8:30am from Horseshoe Farm Park in Rolesville, NC. Payload was recovered at 12:40pm 5 miles north of Centerville just off Hyw 58.

https://www.flickr.com/photos/clubjuggler/albums/72157630135972182