The rocket spec requires us to design a two parachute recovery for Eggbert (the second). This is basic engineering... see this for example...
I have made a super-miniature altimeter...
...that we could use to control the deployment and control the flight time, but first we need to determine basic performance parameters for parachute specs without freezing to death... (it will be 'nuff cold in the hut and I don't want to spend all evening outside dropping parachutes from precarious heights whilst I freeze up…)