SPC-HWX-2_Preliminary_Requirements_Table_26Jan2021.pdf

Preliminary Requirements for the U.S. Coast Guard

Special Purpose Craft – Heavy Weather (SPC-HWX II)

COMDT (CG-731) 26 Jan 2021

The Coast Guard operates four 52-ft Special Purpose Craft – Heavy Weather (SPC-HWX) in the Pacific Northwest. These boats were built starting in the 1950s and are in need of replacement. The replacement boats (SPC-HWX II) need to be able to cross breaking bars and transit offshore in extreme seas with a capability that exceeds that of the 47-ft Motor Lifeboat (MLB)1 in order to conduct Search and Rescue (SAR) missions including towing and persons in water (PIW) recovery. In addition, the new boats will need to be multi-mission capable in order to conduct Ports, Waterways and Coastal Security (PWCS), Law Enforcement (LE) and other missions performed by Coast Guard stations.

Physical Constraints Length 64 ft 0 in maximum overall Beam 22 ft max w/ fendering Draft 7 ft Operating Environment Breaking Surf 25 feet Seas 35 feet Winds 60 knots Performance and Stability Speed, maximum 25 knots Speed, cruising 20 knots Range 500 nautical miles Towing Capacity 350 displacement tons, all sea conditions Stability Self-righting in intact condition (objective self-righting with pilothouse damaged); two compartment hull damage stability Mechanical Systems Propulsion Twin Diesel w/ straight or U/Vee drive to propellers

(no EPA exemptions are planned) Electrical Primary functions (control, navigation, communication) via engine driven

DC power, house loads via diesel generator HVAC Heating and cooling for all manned spaces, heated windows

Arrangements

Hull Monohull with side recesses for SAR operations, prominent fendering system, designed to operate in surf and shed water

Enclosed Pilothouse Arranged with maximum visibility and outfitted with 4 primary crew seats (coxswain, navigator, engineer, and crewmember) with consoles and 4 secondary passenger seats, all shock mitigating

Open Bridge Arranged for control in surf and alongside operations with 4 primary crew seats

Habitability Outfitted for missions up to 3 days including 4 berths, head, small galley, seating for 5 survivors

Towing Prominent towing bit with power capstan; outfitted w/ two DBN towlines:

1200 ft of 4” circ. and 900 ft of 3-1/4” on powered stowage reels

Anchoring Anchor system with powered winch/capstan Equipment Stowage Exterior stowage lockers for mooring lines, towing bridles, fenders and misc. SAR equipment, storage for 2 CG P-6 pumps (in 24” dia. X 28” high containers), interior stowage for SAR equipment including Stoke’s liter

Weapons Capability Forward and aft mounts for M240 automatic weapons, interior lockable stowage for 4 long guns and ammunition

Davits Port and starboard davits with 500 lbs SWL for PIWs and equipment Navigation and Communications Integrated Navigation System Displays at all primary crew seating locations using Scalable Integrated

Navigation System 2 (SINS-2) integrated with AIS Communications Tactical VHF, Tactical UHF, Commercial VHF DSC, Satellite, Loudhailer, Headset Crew Communications System

Notes: 1. USCG 47 MLB has a top speed of 25 knots, is capable of operating in 20 ft surf and 30 foot waves, has a calm water range of 200 NM at 20 knots, and a towing capacity of 150 displacement tons with a 900 ft 3-1/4” DBN towline