John Kovac KM6GKF
Hank, thanks for your email about this.
The GoPro pointed up in my payload box captured the moment. Looking at it, I'm still not sure what happened. Here is a link to the video:
11 of the 12 feet of line running from the parachute to the payload were still on the ground, so the line break had to occur near the parachute. Also still on the ground, separately, was the Stratotrack, with a 10 inch or so piece of line still attached to the antenna loop. It's held in place by the stopper knot tied in the free end of the bowline knot attached to the parachute. It keeps the tracker from sliding down the flight line during flight.
If I had tied a bad knot at the parachute, it should have pulled the tracker and flight line down together on one piece of line. If the line broke below the knot, the tracker should have stayed attached to the balloon by the stopper knot. So I am puzzled by the tracker with a short piece of line still attached to it left behind as well.
Any input appreciated.