Project Horus High altitude balloon project

Horus 20

Technical information:

Launch date 17/1/2012, 02:12 pm
Landing date 17/1/2012, 03:52 pm
Flight duration 1 hour, 40 minutes
Launch site -37.62691, 143.88895
Landing site -38.13865, 144.75316
Flight path WebKMZ
Distance travelled 94.9 km
Maximum altitude 22,040 m
Average ascent rate 5.1 m/s
Impact speed 11.2 m/s
Flight computer MicroNut Flight Computer
GPS module uBlox 6 NEO-6Q + Sarantel GeoHelix antenna
Radio transmitter Radiometrix NTX2 25mW (RTTY)
Telemetry 300 baud RTTY, CRC16 checksum
Video Cameras None
Tracking Ground stations (distributed listener), 2 chase cars, web based tracker


Horus 20 was the first micro-payload launch at 2012, in Ballarat, Victoria. During Project Horus' presentation to the conference attendees, Terry and a local amateur radio operator (Josh Mesilane VK3HGI) filled a 200g red Hwoyee balloon backstage, which was brought out to a field near the conference venue.

Mark, Josh and Joel taking the big red balloon out to the field.

After a brief holding period while Mark readied the telemetry systems, the balloon was launched in front of a crowd of attendees. Conditions at the launch site were quite windy, but the launch went well regardless.

Joel holding the balloon down while Terry readies the payload.

Immediately after launch, Joel, Terry and Mark hopped into Terry's new chase car (Toyota Rav4) and headed off, with Josh following closely behind. The balloon's flight path was predicted to burst at approximately 10km altitude and land just east of the Brisbane Ranges. However, as the flight progressed and continued ascending well above 10km altitude we realised this wasn't going to happen. With the payload passing through 20km altitude, the predicted landing site was well out to sea, in Port Philip Bay. Realising we would have no hope of recovering the payload, we turned around and headed back to Ballarat. The balloon burst at just over 22km altitude, and we pulled over to try and capture the last few sentences as it splashed down.

Mark using a small Yagi to receive the last few telemetry sentences.

The last data received from the payload was a corrupted sentence reporting an altitude of 83m. It's quite possible the payload washed up on a beach near St Leonards, but we haven't heard from anyone yet.