The stratoballoon flight generated both some beautiful pictures
and some awesome data
but only because we recovered the capsule. There were a lot of reasons why this capsule might not have been found, or found intact. What could we have done to make finding the capsule less a matter of chance?
If we were to do this again, I think the first thing would be to be more aggressive about chasing it during its flight. The balloon was at 50,000 feet and rising before it occurred to us to try putting the receiving antenna in the car. Then, when we detected that it was falling, we were still miles away. If we had packed up the vehicles and left as soon as we released (or at least, much closer to that point), we could have been closer to it when it was on its descent. That would hopefully allow us to pick up the signal for longer periods, and greatly narrow the recovery area down.
Another improvement would have been to have a second chase car outfitted with a second receiving station (antenna, software defined radio, laptop, and cellular wifi hotspot), which would have allowed us to position one car in the predicted recovery area prior to launch, and then track the balloon from there. Having two cars driving around hopefully would have doubled the chance that we would have been able to track the capsule all the way to the ground, which would have meant a much better chance of recovering it ourselves.
Third, we should have spent more time researching Automatic Packet Reporting System, or APRS. There is a lot of infrastructure already in place around Michigan for receiving and reporting the positions of things like balloons that are transmitting their position on the APRS frequency, 144.39 MHz (2 meter band). However, by the time Katherine and I found out about this network, we had already purchased the transmitter that worked on the 70cm band and were working to incorporate it into our instrument pack. Changing that out would have taken time and money. If we were to do this again, I think I would start with an APRS-compatible GPS and transmitter combination, and built the rest of the instrument pack around it.
Fourth, the capsule’s transmission antenna, being pointed down to Earth, worked great for most of the flight. However, we knew that once it was on the ground we would probably lose the signal – and we did. In fact, being on the bottom meant that the capsule came down on top of it, crushing it and destroying its ability to talk to us. For a second flight, it might be worth it to see if we can either build a second antenna on the top of the capsule, or even incorporating a second transmitter that could communicate via the cell towers – something that would only operate on the ground (in order to keep within FAA regulations).
Finally, I found myself wanting to post updates about the launch, chase, and recovery, but our laptop was fairly dedicated to receiving and interpreting the updates from the capsule. If I had a smart phone, it would have been nice to set up a Twitter account and use that to post those quick updates.
My hope with this blog post – and with the entire stratoballoon podcast series – that other groups can see what we did, replicate what worked well, and improve upon the rest.