The term "VHF assisted collision" is not new. It is used when an officer of the watch negotiates actions to avoid a collision with another vessel over the radio rather than following the Collision Regulations (Colregs), but ends up colliding with the vessel, usually because of miscommunication between the parties or an agreement to maneuver vessels in a manner contravening the Colregs.
The UK Marine Accident Investigation Board (MAIB) has recently published its report on the collision between the RICKMERS DUBAI and WALCON WIZARD, which was being towed by the KINGSTON in the Dover Straits in January 2014. The authors of the report heavily criticise the over-reliance by the navigating officer on RICKMERS DUBAI on the ship's Automatic Identification System (AIS) equipment.
AIS was phased into commercial shipping approximately 10 years ago, with security concerns being the main driver behind its implementation. Air traffic control has employed a similar system for decades and this system, together with radar, forms the basis of the control of aircraft.
Like all other equipment available to the navigating officer, AIS must be used with caution and, most importantly, in conjunction with other equipment. Crosschecking the information available from the AIS is especially important because of the high risk of errors that may be contained within. Unlike other sources of information, such as visual and radar, the correct functioning of the AIS relies on the equipment on other vessels performing correctly. This is not just confined to the AIS system itself, but also to all the navigational equipment that feeds the system. Of all the information available to the officer of the watch, that which is obtained from the AIS may often be the least reliable.
The MAIB report identifies several factors that contributed to the collision, however it was the reliance by the navigator on RICKMERS DUBAI solely on AIS information for collision avoidance, which contributed most. It is easy to see why, given that neither KINGSTON nor WALCON WIZARD were transmitting AIS data at the time.
The full report can be obtained by following the link below.