back to the Index or the Vehicles page

Description

     The Morrow Project fusion-powered Patrol Boat Mk III is intended for use as a personnel transport or ferry, for reconnaissance of maritime areas, for interdiction of smuggling and infiltration craft, for dive support, and for fire support on shore areas. They were constructed in 1977 and 1978 at Sturgeon Bay, Wisconsin; note there is no Mk I or Mk II in Project service.

     The crew consists of the team leader (skipper), quartermaster (mans a gun in combat), bosun (at helm in combat), observer (radio and radar operator), engineer (mans a gun in combat), and gunner.

     The vehicle has a complete NBC filter and decontamination system combined with heading and air conditioning, and can support its crew while sealed for at least a couple of months with the supplies and equipment on board. Wet and dry suit diving equipment is provided for all six crew members.

     The pilot house is offset to starboard, allowing more deck space for armament, equipment or cargo. There are four pedestal mounts with gun shields -- two forward and two aft -- at the side rails; these can accommodate .50 caliber machine guns, or 40mm grenade launchers. Three hardpoints -- one forward, one aft, and one along the port side -- can accommodate heavier weapons (up to a 40mm Bofors gun), but normally only a single Mk 2 Mod 1 mortar/MG is fitted to Project vessels. These hardpoints may each also be used to mount a HIAB crane.

     The intercom system has four stations:  pilothouse, CIC, engine room, and aft deck (near the mortar ammo box). All but the station on deck have permanently-installed handsets; all four stations have weatherproof jacks for headsets.

     Clear deck space is about 7.5 meters long by 2.5 meters wide; there are two engine room hatches, and a cargo hatch (1.2 x 1.2 meters) into the lazarette space. There are four hoisting eyes, two on each side of the boat.

     Built-in accessory equipment includes a search light, (controlled by the helmsman), identification and navigation lights, LSS-40 loudspeakers, siren, horn, 6" signal lamp, an AutoNav and a Mk 23 gyrocompass, a Raytheon DE736 fathometer, a Lowrance X-3 sonar, a Furono FR802D radar, some sort of automated radar plotting aid, an AN/APR-38 radar detector (the same used on early Wild Weasel aircraft, but with some different frequencies and modes being scanned for) , a refrigerator, freezer, stove and other galley equipment, water filtration/purification system, shower/head cubicle, 378 liter fresh water tank, four electric bilge pumps (also used for fire-fighting and deck washdown), and one hand-operated bilge pump. The mast carries the antenna for the radar and radio.

     An emergency transponder beacon is fitted in the pilothouse, but its battery is disconnected and it's unplugged from the boat's electrical system.

     A dive platform is located on the transom, with a folding ladder leading up to the stern.

     We have two pages for equipment:  important items, and items you may never care about. 

green indicates upholstery or bedding; red indicates curtains

Specifications

Weight: about 28 tons empty; about 37 tons full load

Length: 19.8 meters

Beam:  5.5 meters

Draft: 1.7 meters 

Height from waterline:

• to main deck at pilothouse:  1.5 meters

• to top of the pilot house:  3.9 meters

• to top of radar mast: 6 meters (the mast can be folded down to lie horizontal, level with the top of the pilot house) 

Turning Radius:  75 meters at speed of 20 knots

Stopping Distance:  34 meters from max speed, in 9 seconds 

Max Speed:  26 knots (30 knots is possible at emergency power)

Range:  unknown; it would presumably wear out long before the generators ran out of fuel

Fuel Capacity:  integral to the generators

Engines:  three 650 HP electric motors (one for each propeller shaft), powered by three water-cooled Mk 1 Fusion Generators. Note that the generators can operate at about 10% power level if water cooling is interrupted.

Electrical System:  most systems run on 24 volts DC, but the fusion generators also provide 12 volt DC, 120 volt AC, and 240 volt AC at various outlets; other voltages can be set up with non-standard connections

Batteries: 48 Morrow Project vehicle batteries, enough to run all three engines at full power for 9 minutes

Armament: typically two M2HB machine guns, two M174E3 grenade launchers, one Mk 2 Mod 1 81mm/.50 caliber mortar/gun mount, plus crew individual weapons

Armor:  the hull is aluminum alloy 6.25mm thick (armor value 13); the wheelhouse is 3.2mm thick aluminum (armor value 10). The wheelhouse windows are 8mm thick polycarbonate (armor value 10). Resistweave dodgers can be fitted over all of the guard rails (double thickness, hence armor value 9). There's a video about how effective the armor is!

boat with dodgers fitted

How fast can it go?

Compartments

     From forward to aft: 

• forepeak:  this is the bosun's locker, with spare lines, anchors, and other nautical equipment. There are two vent pipes providing ventilation here; note that this space is not included in the air conditioning/air filtration system on the boat.
  

• crew quarters:  four bunks, six storage bins (three under each lower bunk), and small arms storage. A door leads to the main compartment, and an escape hatch leads up to the forward deck. There are four berth lights, one bulkhead light, and one red light. There are two deck vents, but they are almost always closed.
  

• main compartment:  the galley area, mess, head, CIC, and officer's quarters are all here. Doors lead forward to the crew quarters, or aft to the engine room; a steep set of steps leads up to the pilothouse. Two CO2 extinguishers are fitted here. There are four dome lights, and two red-or-white utility lamps.
  

• the galley area has a sink, two burner electric stovetop, oven, microwave oven, and several shelves, cabinets and drawers. Note that the sink is a "hand-pumped" model, to prevent water wastage, although it does have an electric in-line heater to produce hot water.

• the mess is a table with two padded bench seats; it seats four comfortably, or six very uncomfortably. A chair pulled up to the inboard end will allow five people to eat comfortably. Underneath the aft bench seat is the refrigerator; underneath the forward bench seat is the freezer. The table surface can be unhooked from the wall and lowered down level with the padded bench seats, to form a large sleeping surface (about twice the size of the bunks in the crew quarters).
  

• the head has a stainless steel sink and toilet; the entire cubicle is also a shower stall. There is a 200 liter sewage tank, with an alarm in this compartment and in the pilothouse when it reaches 90% capacity. Tank pumping controls  are in this compartment.
  

• the CIC is a chart table and a couple of shelves along the starboard side of the compartment. The computer, Laserdisc, radar, Autonav, radio direction finder, battery recharger, and some other minor electronics are located here. There's a chair for the observer.

• the officer's quarters has a bed, small desk/shelf, locker, and a folding screen running on an overhead track. 

• engine room:  contains the three electric motors which propel the boat; also a workbench (starboard) and lockers for tools, spares, and manuals. Two doors lead aft through the power compartment; an escape hatch leads up to the deck. There are two large hinged hatches overhead, as well, used to remove or replace large items of equipment. The forward bulkhead has switch boxes and circuit breakers for the electrical systems. The compartment is illuminated by two bulkhead lamps, and two arm lamps (one at each side). Two CO2 fire extinguishers are located here, along with the hand-operated bilge pump.
  

• power compartment:  only about a meter long, this contains the three fusion reactors, most of the electrical batteries, and the water cooling system for the reactors. Two sets of doors lead forward to the engine room, or aft to the lazarette. The outboard areas of this compartment hold extension cords, jumper cables, and portable work lights. Two high-voltage electrical fire extinguishers are located here. Illumination is by two bulkhead lamps (one on each side).
  

• lazarette:  cargo storage, and the rudder motor. A cargo hatch, and escape hatch, are mounted overhead; two doors lead forward through the power compartment. The fresh water tank (378 liters), water purification system, rudder tillers and motor are located here. Racks on the port and starboard side hold 20 liter cans of lubricant. A CO2 fire extinguisher is located here. Illumination is by one bulkhead lamp.
  

     On deck is the pilothouse, with steering and engine controls, indicators and instruments, navigation equipment (including fathometer and radar repeater display), three windshield wipers, cease-fire horn, fire detection warning lights, 1MC broadcast to each belowdecks compartment, general quarters and collision alarms, etc. A door leads out onto the deck; steep steps lead down into the main compartment. There's a dome light, and two red/white utility lights. A CO2 extinguisher is kept here. A horizontal rifle rack, to hold three rifles or shotguns, is mounted on the wall; there are a few drawers and other small-item storage spaces here.

     There is a dry storage space below the main compartment, accessed by two bilge hatches. Ammunition is normally stored here.

fitted with a HIAB crane instead of the Mk II mount at the aft position

Variants

    A version for MARS teams mounts four twin-fifty caliber machine guns (instead of singles) on the four "small tripod" deck mounts, and two of the Mk 2 mortar mounts, plus more equipment suitable to their mission. It doesn't have as much equipment for repair and maintenance.

      The dive boat variant carries two HIAB cranes, and more fire-fighting and dive support gear.