This dataset contains the Underway (UWY) data collected on Linnaeus voyage LI2014_V23. Voyage Title: Transit Hillarys Boat Harbour to Fremantle. The voyage took place on the 3rd December 2014 from Hillarys boat harbour returning to Hillarys boat harbour. The Underway (=continuously recorded) dataset from this research voyage includes Navigation (NAV), Sounder, and se-surface temperature data. NAV data includes GPS (Global Positioning System) measurements of latitude, longitude, ship's direction and speed. Data are stored at 5 second intervals (NetCDF) and both 10 second 5 minute intervals (.csv format), including a 10 second PDR (Precision depth recorder) file in .csv format. Additional information regarding this dataset is contained in the data processing report for this voyage.