The new high-performance fireboat is specifically designed to provide fast emergency response, search and rescue, fire-fighting operations, capability as an on-scene command post, port security, EMS and assistance with diving operations and recovery. The vessel is of all-welded aluminum construction and is ice-strengthened to suit year-round operations in Boston Harbour and surroundings. The vessel is equipped with a large aft swim platform, and thirty Switlik life rafts to facilitate rescue of aircraft crash survivors. The vessel is also fitted with a FLIR thermal imaging system and ample flood lighting for night time operation.
The vessel has been built in accordance with the ABS Guide for Building and Classing High Speed Craft, but was not so classed, and satisfies the requirements for designation as an NFPA Class III fireboat.
The fireboat is designed for a full load response speed of 24 knots, which was achieved during trials, and a low-wake, 12 knot cruising/patrol speed. The powering, sea-keeping, and wake generation characteristics of this semi-displacement hull form were verified by computational fluid dynamic analysis (CFD).
The propulsion system consists of four main engines, each driving a fixed-pitch propeller, with the two inboard engines also connected to the two main fire pumps at the forward end. All four engines are utilized to achieve top speed in an emergency response, and then the two inboard engines are de-clutched from the propellers and used to drive the fire pumps while the outboard engines are used to control the boat's position and heading.
Total installed propulsion power is 2 x 1,450 BHP (2 x 1,080 kW) from two CAT C-32 ACERT engines and 2 x 873 BHP (2 x 650 kW) from two CAT C-18 ACERT engines. Propellers are five bladed, fixed-pitch, driven through ZF models 2000 A and 3050 V reverse-reduction gears on the inboard and outboard shafts respectively. The propeller design was chosen early in the design process for reliable operation in slush ice, which exists at times in the area of operation.
Electrical power is supplied by a pair of CAT C4.4 diesel gensets, each rated 76 ekW.
All engines are EPA Tier II certified.
The Fire-fighting equipment for the RAnger 2400 Class fireboat comprises the following:
Fire pumps: 2 x CounterFire model 250-200-500 pumps, each rated 3,000 U.S. gpm (11,350 l/min) at 150 psi (10 bar), driven off the front of CAT C-18 main engines.