VESSEL REVIEW | Alpine Lakes 20 – Compact, all-weather rescue boat to serve Australia’s Alpine Lakes Region

The Alpine Lakes unit of Australian volunteer search and rescue (SAR) organisation Marine Rescue NSW has taken delivery of a new aluminium rescue boat built by local company Gray's Marine and Welding to a design by CNC Marine.

Alpine Lakes 20 was completed as a compact rescue boat with a high transit speed to facilitate fast deployment as emergency situations arise even in extreme hot or cold weather, with either case occurring regularly in the boat's area of operations. It replaces an earlier, similarly named boat that had previously served with the same unit.

Crew comfort ensured in rough conditions

"When we started planning this vessel, we had some specific criteria to meet due to its planned location in the Alpine Lakes Region," Marine Rescue NSW told Baird Maritime. "It had to be a trailer boat, capable to be launched and retrieved over difficult terrain. Due to the climate, the cabin had to keep the crew protected from the harsh elements of the lake environment."

The operator added that the vessel also had to be capable of dealing with swell and unpredictable water conditions to allow crews to stay out on the water longer when they need to conduct SAR. This then necessitated careful planning and extensive consultation with CNC and Gray's Marine on expectations concerning the vessel.

"It will be on duty primarily in Buckenderra, Lake Eucumbene, where a purpose-built shed is being constructed and rescue crews are on call 24 hours a day. With the vessel stationed in Buckenderra, it will reduce transit time to allow the crew to respond rapidly to emergencies on the water."

"Marine Rescue NSW set some pretty strict standards when it comes to the performance and functionality of a vessel," added Stevyn Gray, owner of Gray's Marine and Welding. "For this specific vessel, we needed to ensure adequate stability to enable rescues to take place in poor conditions while ensuring high standards of performance offshore.

"The hull needed to be developed around how the vessel is used, a large enclosed cabin up forward with a large working deck down aft. This brings forward its own challenges with balancing the need for buoyancy at the bow while still being able to achieve smooth operations in offshore conditions. We managed this by developing a hull with a deeper deadrise so that it was smooth running, paired with larger inverted chines so that they would stay in the water longer as the boat heels over."

"The vessel has a fully enclosed lockable cabin that was designed for comfort and to keep the crew safe and warm," said Liam Hawkins, Marine Designer at CNC Marine. "We designed a bow ladder at the front to enable the crew to retrieve people from the beach or other vessels without them having to enter the water. There is also a side door that also allows for easy access to the vessel for the crew to pull people on board if they need to."

Marine Rescue NSW added that the bow ladder allows easy access to the boat whilst launching and retrieving from the trailer. The deck meanwhile has a standard open layout but with space maximised to accommodate survivors and allow ample room when rendering first aid even in extreme instances such as a full cardiac arrest.

A foldable mast is fitted to reduce the height for travelling and to allow Marine Rescue NSW to store the boat in a shed without having a height restriction.

Versatility even with limited deck space

Alpine Lakes 20 measures 6.8 metres (22.3 feet) long and is also capable of operating in inland waters. Two Suzuki 104kW (140hp) outboard engines propel the boat to regular search speeds of between 15 and 20 knots.

The hull design allows the boat to easily cut through rough and choppy waters, which typically occur in the Alpine Lakes Region. A pronounced chine meanwhile keeps the boat dry and enables it to respond well to helm input.

"The vessel does have capacity to accommodate twin 111kW (150hp) engines if necessary in the future," Marine Rescue NSW told Baird Maritime, "but she already has a top speed of approximately 38 knots with the current setup."

Inside the cabin are seats with shock-mitigating bases. This reduces crew fatigue and the risk of back injury when operating in rough conditions.

The cabin also has an electronics suite that includes a Raymarine radar and a Teledyne FLIR rotating thermal camera. The FLIR camera has a field of view function and target lock to maintain contact with targets in water. This enhances the situational awareness of the crew and provides directional guidance to the point of reference.

"We also installed a Raymarine Yachtsense digital control system," said Marine Rescue NSW. "This allows remote access to the electronics and navigation systems when the vessel is active. We can upload search patterns remotely and troubleshoot software problems and monitor the vessel diagnostics remotely."

In Hawkins' view, there are a number of challenges when designing a vessel of this size to meet AMSA 2C (restricted offshore) operations.

"Essentially, we needed this 6.8-metre hull to perform like an eight-metre (26-foot) or nine-metre (29.5-foot) boat, with a large enclosed cabin and working deck. This posed its own issues with developing a hull that could meet and exceed the seakeeping and stability requirements while maintaining an efficient running as well as ease of operation. We therefore had to ensure that this vessel had the adequate foam on board as well as following all other requirements to build it to 2C Survey."

Hawkins added that the design work on Alpine Lakes 20 provided an opportunity to improve communication with and understanding of the end user as well as to streamline the build process for the yard. He said this was accomplished by enabling full insight into the 3D design process, with multiple iterations and hull refinements all conveyed through a 3D viewer, which essentially gave the builder and the end user an insight into each part before the build commences.

"When it comes to small vessels that are meant to push boundaries, it is important to have clear understanding of how the vessel is to be operated as well as any potential load cases it might undertake," he told Baird Maritime. We do this running countless stability analyses during the hull refinement and iteration process to ensure no matter what situation may be faced, the vessel will perform as the crew expects."