Thanks to gliderpilot from the Adafruit forums for sharing this DIY variometer project. Check out more on the build here.

An essential instrument in the cockpit of a glider is a rate-of-climb indicator. The usual mechanical indicator has slow response meaning that it may not detect small areas of rising air… the fuel that keeps gliders aloft.

Using an Arduino UNO R3 and an Adafruit MPL3115A2 (Product 1893), I made a fast responding rate-of-climb indicator with an audio output. The full story (including a couple of unsuccessful analog attempts) can be found at: http://theradioboard.com/rb/viewtopic.php?f=8&t=6061

Read more.

Featured Adafruit Product!

MPL3115A2 – I2C Barometric Pressure/Altitude/Temperature Sensor: This pressure sensor from Freescale is a great low-cost sensing solution for precision measurement of barometric pressure and altitude. The MPL3115A2 has a typical 1.5 Pascal resolution, which can resolve altitude at 0.3 meters (compare to the BMP180 which can do 0.17m). It has some upsides compared to the BMP180, such as interrupt outputs for ultra-low power usage, and its also a heck of a lot easier to read altitude with a built in altimeter calculation – no calibration reading and calculating required. As a bonus, there’s even a fairly good temperature sensor with ±1°C typical accuracy (±3°C max). Read more.