Solar unmanned balloon launch
July 21, 2013
On July 21, 2013, faculty from UND's Computer Science Dept., and Regional Weather Information
Center launched a prototype solar-powered hot-air balloon. The balloon carried
no payload and was not tracked, being flown as a proof-of-concept for possible
later flights of larger balloons.
The balloon was launched at 1:00 pm local time. The air temperature was about 80F, with light and
variable winds. The balloon was filled from a hair drier, with the launch team standing on the lee side of
Clifford Hall as a shelter from the wind.
The balloon envelope was a 10' diameter "tetroon" (tetrahedral balloon) made from 16 black plastic trash
bags, each with a capacity of 33 gallons (0.7 mil thickness),
1 roll of masking tape (55m length, 18mm width), and
4 feet of duct tape for lift loop and nozzle reinforcement.
Since the balloon and payload weighed less than 4 pounds, the flight was exempt from most of the
FAA FAR part 101 regulations regarding free-flight balloons.
After launch, the balloon ascended at approximately 3 to 4 feet per
second. The balloon was tracked by naked eye until approximately
20 minutes after launch. The balloon was still ascending and
travelling down-wind at the time.
10' tetroon:
