The flow measurement device of the present invention incorporates numerous novel features. For example, the device includes a displacement measuring device to measure the position of a movable plate member, a self-oscillation dampener to dampen oscillations of the plate member, one or more stiffening members engaging or incorporated into the plate member to increase the resonant frequency of the plate member and reduce flutter, and a conduit providing for differing directions of air flow at different points along its length to eliminate the effects of gravity on flow measurements.