Extra Resources for You & Sea Students Course Material Please click on the individual course boxes below to access the material Small Ships Navigation & Radar Boatmaster Prep mASTER 200GT PREP MCA Workboat Stability ECDIS VHF & GMDSS RADIO Yachtmaster Theory Human Element & Leadership Management Useful Links Stability Guidance Admiralty chart symbols & abbreviations IRPCS Rules Navigation Videos Rocks, wrecks & obstructions Fixing a position Leeway Magnetic Variation calculating the tidal hour Course to Steer Introduction to the Chart Deviation using tidal diamonds plotting a position tidal theory estimated position