Here’s a cool DIY tool for para-gliders and alike, learn how to make an Alti-Variometer. I’ve actually seen a para-glider who crashed into a tree by the highway the other week. If he had landed on the highway, I am sure he could have easily crashed onto on-coming cars. Perhaps this Alti-variometer could have prevented him going awry in the first place.
[Vlad-Andre] used some of his free time to build an alti-variometer. He does some para-gliding near restricted air space and wanted a backup altitude warning that would help keep him below the mandated altitude. His solution uses the SparkFun Weather Board in conjunction with their BlueSMiRF dongle to measure altitude and transmit it via Bluetooth. From there, he wrote a program to grab the transmitted data with his cell phone and display the information. His application also has the ability to set altitude warnings and log changes over time.