Solar unmanned balloon launch
December 9, 2013
On December 9, 2013, students and faculty from UND's Computer Science Dept., Regional Weather Information
Center, Atmospheric Sciences Dept., and Aviation Dept. launched a solar-powered hot-air balloon. The balloon carried a
passive radar reflector, which was tracked using a Doppler weather radar system.
The balloon was launched at 11:30 am local time. The air temperature was -9F, with westerly winds at 15 mph
and gusting to 17. The balloon was filled from a hair drier, with the launch team standing on the lee side of
Streibel Hall as a shelter from the wind.
The balloon envelope was a 16' diameter "tetroon" made from 36 black plastic trash bags, each with a
capacity of 30 gallons (0.5 mil thickness),
2 rolls of masking tape (55m length, 18mm width), and
6 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 6 feet per
second. The balloon was tracked via radar to an altitude of over 38,000 feet AGL at launch + 90 minutes.
The track was lost at that point, but the balloon was still ascending at a nearly-constant rate.
The passive radar reflector payload carried contact information in case the payload was
later found. See below for recovery update.
Filling:
Launch:
Tracking:
Altitude vs. Range:
Update: May 5, 2014 The balloon was found near Aurora, MN, a distance of about 258 miles from the launch site.
This image, provided by Mapquest.com, shows the launch site at "A", and the landing
site at "B". Note: the blue line is NOT the balloons flight path, and may be disregarded.
