Bridge Watchkeeping — Officer of the Watch Training

The officer of the watch (OOW) bears responsibility for the safe navigation of the vessel during their watch. The primary duties are maintaining a proper lookout, monitoring the ship's position, and taking early action to avoid collision with other vessels. Bridge Watch is a radar-based game that simulates these duties in real time.

CPA and TCPA

The Closest Point of Approach (CPA) and Time to Closest Point of Approach (TCPA) are the fundamental parameters for assessing collision risk. They are calculated from relative motion plots (the MRAV — Most Recent Approach Vector):

• Plot the target's position at intervals on the radar
• The relative motion line, extended, passes through the Own Ship position at the CPA distance
• Divide the distance to CPA by the relative speed to get TCPA
• If CPA is less than your company's safe passing distance (typically 0.5–2 nm), take action

Watchkeeping standards (STCW)

The International Convention on Standards of Training, Certification and Watchkeeping for Seafarers (STCW) sets minimum rest requirements for watchkeepers. Under STCW A-VIII/1, officers must have at least 10 hours of rest in any 24-hour period and at least 77 hours in any 7-day period. Fatigue is a major contributor to maritime casualties — the Bridge Watch game is timed to reflect realistic watch durations.