Add to ORKGA new instrument known as the NACA three component accelerometer is described in this note. This instrument was designed by the technical staff of the NACA for recording accelerations along three mutually perpendicular axes, and is of the same type as the NACA single component accelerometer with the addition of two springs and a few minor improvements such as a pump for filling the dash-pots and a convenient method for aligning the springs. This note includes a few records as well as photographs of the instrument itself