Project Horus High altitude balloon project

Horus 1

Technical information:

Launch date 5/2/2010, 14:33
Landing date 5/2/2010, 16:30
Flight duration 2 hours, 57 minutes
Launch site -35.1276, 138.8477
Landing site -35.0382, 139.2575
Flight path Web, KMZ
Distance traveled 38.6 km
Maximum altitude 29,606m
Average ascent rate 8m/s
Impact speed 15m/s (54km/h)
Flight computer Arduino Duemilanove
GPS module Trimble Lassen IQ
Radio transmitter Radiometrix NTX2 25mw
Camera 1 Panasonic Lumix DMC-LZ2
Camera 2 Kodak Easyshare C310
Sensors Internal & external temp, humidity, atmospheric pressure
Telemetry 50 baud RTTY, XOR checksum
Tracking Ground stations (distributed listener), 3 chase cars, web based tracker
Backup systems SPOT satellite transponder, radiosonde


Horus 1 was my first high altitude balloon launch - I sourced a couple of cameras from eBay & built a flight computer around an Arduino and Ladyada's GPS shield with a Trimble Lassen IQ. Inspired by the usccess of UKHAS members, I bought a radiometrix NTX2 and ham radio receivers for telemetry.

Horus 1 included internal and external temperature sensors, as well as a relative humidity sensor, and an atmospheric pressure sensor (though this only had a range to about 15km altitude).

Overall the launch went smoothly, and the payload was receovered OK. The major failings in the launch were that the camera lens filters quickly got fogged up & ruined most of the photos, ascent rate calculations were slightly off, resulting in a much higher ascent rate than planned, and the balloon got tangled around the parachute/radar reflector after burst, resulting in a very high impact speed.

More details in the blog entry.

Lessons learned:

  • Balloon filling - more care to be taken with inflation counterweight, bring some scales next time!
  • Lens mist - flush the payload with helium to remove atmosphere and moisture
  • Line tangling - increase spacing between balloon & everything else


Horus 1 flight data