COLREGs Analysis
Vessel Title
Active Hardware
Description & Fog Signal
NavLights 3D 🚢
Welcome to the zero-friction interactive COLREGs simulator.
• Drag the canvas to rotate your view.
• Scroll/Pinch to zoom in and out.
• Use the Sidebar to search configurations, change to Twilight, or play exam mode.
• No login required. Fast, simple, and accurate.
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What is the NavLights 3D – Interactive COLREGs Visualizer?
The NavLights 3D – Interactive COLREGs Visualizer is a dynamic, browser-based environment designed to bridge the gap between static manual study and the rapid-fire visual identification required during real-world night navigation. By allowing users to manipulate 3D vessel models and observe their proper navigation lights and day shapes from any angle, it solidifies the understanding of COLREGs Part C (Lights and Shapes).
All maritime tools on this site are for training purposes only, and there is no real-time integration with any physical hardware or vessels.
Key Features & Benefits
360-Degree Interactive Rotation
Freely rotate 3D vessel models to instantly understand how navigation lights and aspect angles change based on your relative position.
Comprehensive COLREGs Scenarios
Quickly master the visual profiles for vessels underway, at anchor, towing, fishing, constrained by draft, or restricted in their ability to maneuver.
Day and Night Mode Toggle
Seamlessly switch between nighttime light configurations and their corresponding daylight shapes to ensure well-rounded rule retention.
Arc of Visibility Indicators
Visually inspect the strict degree sectors required for masthead lights, sidelights, and sternlights to grasp the mechanics of collision avoidance.
Practical & Educational Uses for a 3D Navigation Lights Visualizer
OICNW & USCG Exam Preparation
An invaluable study aid for deck cadets and maritime students who must flawlessly identify vessel lights and shapes during licensing exams.
Bridge Watchkeeping Familiarization
Helps active junior officers and lookouts refresh their nighttime visual identification skills before taking over a navigational watch.
Recreational Boater Safety
Enables recreational sailors and weekend cruisers to confidently interpret the lights of commercial traffic they may encounter after dark.
Maritime Academy Instruction
Provides instructors with a dynamic visual aid to demonstrate complex collision-course scenarios and vessel aspects to a classroom.
The Importance of Navigation Lights in Modern Seafaring
Even in an era dominated by advanced marine electronics like Radar, ARPA, and AIS, the fundamental ability to visually identify a vessel’s navigation lights remains a non-negotiable pillar of maritime safety. Mastering these visual cues is what separates a reactive radar-watcher from a proactive, situationally aware mariner.
The First Line of Defense at Night
Navigation lights are the primary visual language of the sea from sunset to sunrise. They allow a watchkeeper to immediately determine a vessel’s heading, relative aspect, and right-of-way. While a radar screen shows a target’s position, the immediate, intuitive grasp of a “red light crossing from starboard” triggers the instant mental application of the Rules of the Road.
Deciphering Vessel Status
Beyond just showing where a ship is pointing, COLREGs lights and shapes communicate critical information about a vessel’s operational status. A quick visual check tells you if a vessel is towing a heavy load, engaged in fishing, or completely broken down (Not Under Command). This immediate situational awareness dictates your maneuverability and safety margins long before a radio call is made.
Beyond Electronic Reliance
Technology at sea is vulnerable to power outages, sensor blindness, and GPS spoofing. When screens fail or smaller vessels aren’t broadcasting AIS, your eyes become the only reliable navigational sensor. Visual proficiency in reading ship lights ensures that a watchkeeper can maintain safe navigation in the lowest-tech, highest-risk scenarios, upholding the international standards that keep global waters safe.