If you study any page one before starting your own design for a parachute, this would be the page to look over. Although problems are generally unique to situations, I hope by telling you the problems I encountered that you’re able to prevent problems from occuring.
Problem: The color of your material. Parachutes are bright colors for a reason. It was a mistake to use a clear material for my chute because that’s one of the easiest ways to spot yor rocket as it falls down to the earth. Either use a bright material or paint it.
Problem: Volume constraints. Unless you have a big rocket, the amount of space you have available should always be in the back of your head. For me, the cords took up the most room and I ended up using a much smaller gauge string than I initially intended to use. Just be conscious of how much room you have to work with.
Problem: Diameter vs. Radius. Make sure that you don’t get diameter and radius confused! It’s extremely easy to do — diameter is equal to 2 * radius. I switched back and forth using radius and diameter several times, so be on the lookout for the proper measurement.
Problem: Metric units??. That’s right folks, we’re using metric units. If you ever use pounds, mph, or inches in any formula then you aren’t doing it right. You MUST convert everything to metric — which means all units should be in kilograms, newtons, meters, m/s, or m/s^2 — no exceptions. If you want to use inches in your actual design that’s fine, but just be aware that the equations I’ve given you are for metric units only.
Problem: Trying to be too accurate. The overall purpose of this project was to just have fun using physics formulas to determine an estimate for a good parachute size. At times I rounded up, cut corners, etc. and in the end I stretched the meaning of the word ‘estimate’ — but the point is don’t worry about things not being 100% perfect, just remember to have fun with it.
Next: Testing and Conclusion