gives you three three numbers at any given time measuring the angular velocity around the three main axes of the helicopter if that's you know if you mounted axis aligned then three axis accelerometer accelerometers measure acceleration but not exact acceleration it's a little trickier than that Adashi measures all zeros in freefall so if you're free falling an accelerometer measures all zeros and anything that you do that's not free-falling for example if you're standing on the ground your accelerometer will measure 9.81 m/s^2