I have a Nano, a Neo-6 GPS, an SD card, and BME-280. I'm wanting to measure rate of descent of different parachute designs I'm working on. What would be the calculations of the data gathered by the BME-080 (for altitude changes). Could I use the GPS for the rtc to timestamp each data sampling? I'd have to collect several per second for an accurate depiction of the rate. Should i just get a pitot tube and not do the calcuations?