MM01 - 2018-04-14
Mark (KN4IUD) made a launch from Punta Gorda Florida. After an hour of ascent, the balloon slowly descended to Hardee County. The flight lasted 2 hours 15 minutes and covered 16 miles.
To add helium capacity, the Qualatex 36 balloon was stretched over a couple of days. Doug provided a program to control the air pump so that high and low pressures were automatically controlled. The circumference was increased 1.5 inches.
To prevent excess internal pressure, the balloon was fitted with a hose that had a .035” vent hole. Pressure testing showed the internal pressure would not rise above 1,000 pascal.
The balloon was pre-filled with more helium than what was required at launch. The leak rate was monitored over 8 days, with an average of 1.3 grams of lift force lost per day. I could not find a leak.