Discuss Special problems in navigation involving Ship identification.

Of course. This is an excellent and critical topic in modern maritime operations.

Ship identification is a fundamental pillar of safe navigation, collision avoidance, and maritime security. While modern technology like the Automatic Identification System (AIS) has revolutionized this process, it has also introduced new complexities and vulnerabilities. The “special problems” arise when the methods used for identification fail, are misleading, or are actively manipulated, leading to dangerous and confusing situations at sea.

Here is a discussion of the special problems in navigation involving ship identification, broken down by their source.

1. Failures and Limitations of Technology

The primary tools for electronic identification are AIS and Radar/ARPA. Both have significant vulnerabilities.

A. AIS-Related Problems (The Most Common Source of Issues)

AIS transmits static data (Name, IMO number, MMSI, dimensions) and dynamic data (Position, Course, Speed). Problems arise when this data is incorrect or unavailable.

• Deliberate Deactivation (“Going Dark”): Vessels engaged in illicit activities—such as sanctions evasion, illegal fishing, or smuggling—will often switch off their AIS transponders to avoid detection by authorities. For a navigator on another vessel, this creates a “radar-only” target with no identity, making it impossible to call them by name on VHF or assess their intentions based on vessel type.
• AIS Spoofing and Manipulation: This is a more malicious problem. A vessel can deliberately transmit false information.
  • Identity Spoofing: A ship can broadcast the identity (MMSI, name) of another vessel to conceal its own. This is common in sanctions evasion, where a tanker might take on the identity of a cargo ship to enter a port undetected.
  • Location Spoofing (GNSS/GPS Spoofing): A vessel’s AIS position is derived from its GPS. If the GPS signal is spoofed, the AIS will broadcast a false location. This can create “ghost ships” on a navigator’s screen, showing a vessel where none exists, or it can mask the true location of a real vessel, creating a severe collision risk. For example, multiple ships might appear to be circling a port they are not actually near.
• Data Input Errors: A simple human error can cause significant confusion. A crew member might incorrectly input the ship’s name, destination, or navigational status (e.g., “Underway using engine” vs. “Restricted in Ability to Maneuver”). This can lead other vessels to make incorrect assumptions about the ship’s intentions or capabilities.
• Equipment Failure: Like any electronic device, an AIS unit can fail. This results in a loss of transmission, making the vessel “dark” to others, or it could transmit corrupted data.

B. Radar/ARPA Limitations

Radar is a primary tool for collision avoidance, but it does not inherently identify a target.

• No Positive Identification: A radar target is just a blob on a screen. It provides range, bearing, course, and speed, but it cannot tell you the ship’s name or type. The process of correlating a radar target with an AIS target is crucial, but this is where problems begin.
• Target Swapping: In dense traffic, an Automatic Radar Plotting Aid (ARPA) can get confused. It might be tracking one vessel, but if another vessel passes very close to it, the ARPA system might “swap” the tracking data, suddenly assigning the course and speed of the second vessel to the first. If this happens, the navigator’s understanding of the situation is instantly compromised.
• Inability to Detect Small Targets: Small vessels (especially fiberglass fishing boats or yachts) may not have a strong radar echo and can go undetected, making them impossible to identify by any means other than sight.

2. The Human Element and Procedural Failures

Even with perfect technology, human error and procedural breakdowns create dangerous identification problems.

• Mistaken Identity on VHF Radio: This is one of the most classic and dangerous problems. A watch officer sees a developing close-quarters situation and hails the other vessel on VHF Channel 16.
  • The Ambiguous Call: “Vessel at three miles on my port bow, this is Motor Vessel Atlantic…” In a busy shipping lane, there could be three vessels on the port bow at similar ranges. The wrong vessel might answer, and the two ships will agree on a maneuver (e.g., “I will alter course to starboard”) that is completely irrelevant to the actual vessel posing the collision risk. This can, and has, led to fatal collisions.
  • The Confirmation Bias: The watch officer expects a certain vessel to be the one they need to talk to, and they may misinterpret a response or fail to verify the identity of the ship that answered their call.
• Language Barriers: The international nature of shipping means that clear communication is not guaranteed. A misunderstanding due to accent, vocabulary, or non-standard phrases during an identification attempt on VHF can be just as dangerous as no communication at all.
• Over-reliance on AIS (Complacency): The “AIS-assisted collision” is a modern phenomenon. Navigators can become so focused on the AIS data on their screen that they fail to use other means to verify a situation. They trust the AIS-reported course and speed, failing to look out the window to see that the vessel is actually turning, or they fail to acquire it on radar. They are navigating the screen, not the real world.

3. Environmental and Situational Challenges

The environment itself can make identification difficult or impossible.

• High-Density Traffic: In areas like the Singapore Strait or the English Channel, the sheer number of targets can be overwhelming. A navigator’s screen can be saturated with dozens of AIS targets, making it extremely difficult to correlate them with radar echoes or visual sightings. The risk of misidentifying a specific, threatening target is exceptionally high.
• Restricted Visibility: In fog, heavy rain, or darkness, visual identification is impossible. Navigators must rely solely on electronic means. This makes them completely vulnerable to the technological and human errors described above. You cannot visually confirm that the ship you are talking to on the VHF is the one whose lights you see faintly through the mist.
• Physical Obscuration: A large vessel (like an Ultra-Large Container Ship) can physically block a smaller vessel from sight and radar. The smaller vessel may have AIS, but the navigator on a third ship won’t be able to visually confirm its position, creating a dangerous situation, especially if the smaller vessel emerges suddenly from behind the larger one.

A Scenario Illustrating the Problem

Imagine this cascade of failures:

1. The Situation: M/V Navigator is in a busy channel at night. An ARPA alarm sounds for a target (Target A) on a collision course.
2. The Flaw: The navigator looks at the AIS overlay. There is an AIS target for a tanker, M/V Goliath, near the radar echo. He assumes Target A is the Goliath.
3. The Call: He calls M/V Goliath on VHF. The Goliath responds, and they agree to a port-to-port passing. The navigator on M/V Navigator feels the situation is resolved.
4. The Hidden Danger: Unseen by the navigator, a small fishing vessel with a weak radar reflector and its AIS turned off (Target B) was the actual source of the ARPA alarm. The M/V Goliath (Target A) was on a parallel course and was never a risk.
5. The Result: The M/V Navigator alters course as agreed, believing he is avoiding the Goliath, but this maneuver takes him directly into the path of the unidentified fishing vessel.

Mitigation Strategies

To combat these special problems, good seamanship dictates a multi-layered approach:

1. Cross-Verification (The Golden Rule): Never rely on a single source of information. Information from AIS should always be cross-referenced with Radar/ARPA, visual sightings, and VHF communication.
2. Proper VHF Procedure: When hailing a vessel, be as specific as possible. Use the ship’s name if known from AIS. If not, use position, course, and speed relative to a known landmark (e.g., “Westbound vessel passing Buoy 12…”).
3. Active Skepticism: Treat electronic data with professional skepticism. Question information that seems unusual (e.g., a “fishing boat” AIS target moving at 30 knots).
4. Vessel Traffic Services (VTS): In busy areas, VTS acts as an independent shore-based authority that can help identify vessels and de-conflict traffic.
5. Visual Lookout: Technology is an aid to, not a replacement for, the human eye. A vigilant lookout is the ultimate defense against misidentification.