Argh. As someone who's done this and is actively involved in the UKHAS (<a href="http://ukhas.org.uk/" rel="nofollow">http://ukhas.org.uk/</a>) this article annoys me. People have been doing this stuff for years, and here we have someone who seems to just not have bothered to learn about how to track a balloon using amateur radio, GPS altitude/speed limits, best practices in terms of the parachute and balloon rigging, and most importantly this article does not once mention the FAA.<p>There's no indication that he was aware of FAA regulations (FAA Part 101) on this type of launch. So, no consideration of payload weight, density, ...<p>Also, he does appear to have use a trajectory predictor but only to figure out where he was going to get his balloon back and not for predicting the path through restricted airspace etc.<p>There's a large community of people out there in the UK and US who are happy to help people get started doing this sort of thing. Please shout out for assistance!<p><a href="http://ukhas.org.uk/general:beginners_guide_to_high_altitude_ballooning" rel="nofollow">http://ukhas.org.uk/general:beginners_guide_to_high_altitude...</a>