VESSEL REVIEW | DHB Diligent – HVO-powered pilot/patrol boat to serve UK's Port of Dover
When the Port of Dover in the UK needed a modern pilot boat, it selected Holyhead Marine Services of North Wales for the construction of the new vessel. The result is DHB Diligent, the first new pilot boat to enter service at the Port of Dover in nearly 20 years.
The 15-metre (49-foot), FRP-hulled DHB Diligent has already begun providing pilot transfer services and conducting patrols of port waters on behalf of the Dover Harbour Board. Pilot transfer support is being provided for the many vessels that visit the Port of Dover, from small leisure boats and yachts to large freighters and cruise ships.
Compact, multi-role platform for various harbour support duties
“We required a new pilot vessel to replace the existing 28-year-old Director,” Port of Dover told Baird Maritime. “The overall brief was for a multi-role vessel that can undertake various duties including harbour patrol, infrastructure inspections, engineer transport to and from breakwaters, line handling, and VIP tours in addition to pilot transfers.”
The boat also needed to possess an in-built monitoring system, hence the installation of an advanced remote real-time monitoring system supplied by AST Reygar.
The system provides data on parameters such as fuel consumption, emissions, and health of critical components. This then enables the crew to adjust operating profiles accordingly and to schedule maintenance before components could experience serious failure.
To comply with the port’s “net zero” targets, the new vessel was required to be as environmentally efficient as possible, compliant with IMO Tier III NOX emission regulations, and able to run on hydrotreated vegetable oil (HVO).
To further enhance fuel efficiency, lower emissions and improve comfort, the boat adopts a refined hull design capable of generating reduced slamming while underway.
“The vessel is available 24 hours within the port to respond to on-water emergencies and VTS policing when tasked,” Port of Dover said. “It is also the duty pilot vessel for carrying out transfers for visiting cargo and cruise vessels.”
Port of Dover has traditionally purchased purpose-built pilot vessels and then adapted these for other roles to meet operational demands. DHB Diligent is an exception, being the first purpose-built, multi-function pilot vessel purchased by the port.
“The biggest challenge was in ensuring the vessel was able to meet some conflicting demands on usage, ensuring enough suitably sized bollards were available for line handling and emergency towage, as well as moving the deck house forward to provide an ample storage/viewing platform aft.”
DHB Diligent is powered by two Scania DI13 IMO Tier III engines that each produce 368 kW (494 hp) and are connected to ZF 510V gearboxes. HVO is supplied by a 1,600-litre (350-gallon) tank.
Full electronics suite for safe all-weather navigation
The rest of the electronics suite meanwhile includes two TimeZero multi-function displays (MFDs), a radar, AIS and a satellite compass from Furuno and radios from Sailor. Also fitted on board are a 24v system switched by an EmpirBus NXT electrical switching and distribution system and a Victron Phoenix Multi-Plus inverter/charger.
“The EmpirBus NXT electrical switching and distribution system consists of five separate nodes linked by an NMEA 2000 network,” Port of Dover told Baird Maritime. “Each output from a node has a programmable software fuse and features undercurrent protection as well as soft start/stop.
“The nodes are capable of being electronically dimmed and of driving complex loads such as LED lighting. Each node consumer can be switched by either of the two MFDs in the wheelhouse, physical switches, or on the node itself.”
DHB Diligent is operated by a crew of two and has seating for up to six pilots/passengers in a wheelhouse fitted with outside handrails for greater safety and reverse-angled windscreens to reduce glare. It is being used primarily within Dover Port limits.
