Abstract: An apparatus for measuring aerodynamic performance is provided, including a batten; a plurality of pressure differential sensors positioned on the batten, each of the sensors having a first port for exposure to a first pressure and a second port for exposure to a second pressure; and a plenum positioned so that each of the first ports is exposed to a pressure within the plenum. The batten is positioned on a sail. The sensors may be in communication with a computer and the sensors may be networked in an asymmetric daisy chain network for uplink communications from the computer and networked in parallel as a bus for downlink communications to the computer.