In the picture immediately above, you can see the XBee accelerometer mounted inside the fuselage of a radio-controlled airplane.

We found two problems with this setup: the vibration and electrical noise from the motor were significant, and the XBee uses the same 2.4GHz band as the controller. I had my receiver near the transmitter, and I suspect that cross-talk between the two may have lessened the range of the XBee, but we could still get some useful information as long as the plane was close.

The graph shown at top right is a loop from near-level flight. You can see the initial increase in acceleration as the plane enters the loop, then the relatively low acceleration at the top of the loop, and finally the high acceleration at the exit. The occasional large times between measurements are due to dropped packets. (RF Interference?)

The largest acceleration measured on this plane was roughly 6 g’s. On a smaller plane (not shown here) we measured 7.1 g’s, inverted!

Special thanks to JP Woolley of A Main Hobbies for spending his morning flying around the park for us.