I have split the research for the High Altitude Balloon (HAB for short) into two parts. The first is researching balloon envelopes and the second the payload that will be sent up.
I have decided to try and make my own balloon envelopes out of mylar instead of using latex weather balloons. This is due to the fact that they will have to be made this way as the payloads are scaled up. Trying to find a 50 – 100 metre latex balloon would be quite costly, if not impossible. With this in mind, I thought the first flight would be used to see how effective a home-made Mylar envelope is and whether or not it would handle the pressures and temperatures at near space altitudes.
The payload for the first flight will be a basic GPS transmitter that will sent back its coordinates on the 433MHz band. It will also monitor its own altitude and be responsible for destroying the envelope and/or deploying the parachute in the event of the balloon reaching a stable altitude and not bursting. This should prevent the balloon being carried away out of recovery range. I am undecided as to whether or not I will send up a camera on the first launch or save that for a later date.
More details to come.